matplotlibcpp.h

#pragma once
 
// Python headers must be included before any system headers, since
// they define _POSIX_C_SOURCE
#include <Python.h>
 
#include <algorithm>
#include <array>
#include <cstdint> // <cstdint> requires c++11 support
#include <functional>
#include <iostream>
#include <map>
#include <numeric>
#include <stdexcept>
#include <string> // std::stod
#include <vector>
 
#ifndef WITHOUT_NUMPY
#define NPY_NO_DEPRECATED_API NPY_1_7_API_VERSION
#include <numpy/arrayobject.h>
 
#ifdef WITH_OPENCV
#include <opencv2/opencv.hpp>
#endif // WITH_OPENCV
 
/*
 * A bunch of constants were removed in OpenCV 4 in favour of enum classes, so
 * define the ones we need here.
 */
#if CV_MAJOR_VERSION > 3
#define CV_BGR2RGB cv::COLOR_BGR2RGB
#define CV_BGRA2RGBA cv::COLOR_BGRA2RGBA
#endif
#endif // WITHOUT_NUMPY
 
#if PY_MAJOR_VERSION >= 3
#define PyString_FromString PyUnicode_FromString
#define PyInt_FromLong PyLong_FromLong
#define PyString_FromString PyUnicode_FromString
#endif
 
namespace matplotlibcpp {
namespace detail {
 
static std::string s_backend;
 
struct _interpreter {
    PyObject* s_python_function_arrow;
    PyObject* s_python_function_show;
    PyObject* s_python_function_close;
    PyObject* s_python_function_draw;
    PyObject* s_python_function_pause;
    PyObject* s_python_function_save;
    PyObject* s_python_function_figure;
    PyObject* s_python_function_fignum_exists;
    PyObject* s_python_function_plot;
    PyObject* s_python_function_quiver;
    PyObject* s_python_function_contour;
    PyObject* s_python_function_semilogx;
    PyObject* s_python_function_semilogy;
    PyObject* s_python_function_loglog;
    PyObject* s_python_function_fill;
    PyObject* s_python_function_fill_between;
    PyObject* s_python_function_hist;
    PyObject* s_python_function_imshow;
    PyObject* s_python_function_scatter;
    PyObject* s_python_function_boxplot;
    PyObject* s_python_function_subplot;
    PyObject* s_python_function_subplot2grid;
    PyObject* s_python_function_legend;
    PyObject* s_python_function_xlim;
    PyObject* s_python_function_ion;
    PyObject* s_python_function_ginput;
    PyObject* s_python_function_ylim;
    PyObject* s_python_function_title;
    PyObject* s_python_function_axis;
    PyObject* s_python_function_axhline;
    PyObject* s_python_function_axvline;
    PyObject* s_python_function_axvspan;
    PyObject* s_python_function_xlabel;
    PyObject* s_python_function_ylabel;
    PyObject* s_python_function_gca;
    PyObject* s_python_function_xticks;
    PyObject* s_python_function_yticks;
    PyObject* s_python_function_margins;
    PyObject* s_python_function_tick_params;
    PyObject* s_python_function_grid;
    PyObject* s_python_function_cla;
    PyObject* s_python_function_clf;
    PyObject* s_python_function_errorbar;
    PyObject* s_python_function_annotate;
    PyObject* s_python_function_tight_layout;
    PyObject* s_python_colormap;
    PyObject* s_python_empty_tuple;
    PyObject* s_python_function_stem;
    PyObject* s_python_function_xkcd;
    PyObject* s_python_function_text;
    PyObject* s_python_function_suptitle;
    PyObject* s_python_function_bar;
    PyObject* s_python_function_barh;
    PyObject* s_python_function_colorbar;
    PyObject* s_python_function_subplots_adjust;
    PyObject* s_python_function_rcparams;
    PyObject* s_python_function_spy;
 
    /* For now, _interpreter is implemented as a singleton since its currently not
       possible to have multiple independent embedded python interpreters without
       patching the python source code or starting a separate process for each.
       [1] Furthermore, many python objects expect that they are destructed in the
       same thread as they were constructed. [2] So for advanced usage, a `kill()`
       function is provided so that library users can manually ensure that the
       interpreter is constructed and destroyed within the same thread.
 
         1:
       http://bytes.com/topic/python/answers/793370-multiple-independent-python-interpreters-c-c-program
         2: https://github.com/lava/matplotlib-cpp/pull/202#issue-436220256
       */
 
    static _interpreter& get() { return interkeeper(false); }
 
    static _interpreter& kill() { return interkeeper(true); }
 
    // Stores the actual singleton object referenced by `get()` and `kill()`.
    static _interpreter& interkeeper(bool should_kill) {
        static _interpreter ctx;
        if (should_kill)
            ctx.~_interpreter();
        return ctx;
    }
 
    PyObject* safe_import(PyObject* module, std::string fname) {
        PyObject* fn = PyObject_GetAttrString(module, fname.c_str());
 
        if (!fn)
            throw std::runtime_error(std::string("Couldn't find required function: ") + fname);
 
        if (!PyFunction_Check(fn))
            throw std::runtime_error(fname + std::string(" is unexpectedly not a PyFunction."));
 
        return fn;
    }
 
  private:
#ifndef WITHOUT_NUMPY
#if PY_MAJOR_VERSION >= 3
 
    void* import_numpy() {
        import_array(); // initialize C-API
        return NULL;
    }
 
#else
 
    void import_numpy() {
        import_array(); // initialize C-API
    }
 
#endif
#endif
 
    _interpreter() {
 
        // optional but recommended
#if PY_MAJOR_VERSION >= 3
        wchar_t name[] = L"plotting";
#else
        char name[] = "plotting";
#endif
        Py_SetProgramName(name);
        Py_Initialize();
 
        wchar_t const* dummy_args[] = {
            L"Python", NULL}; // const is needed because literals must not be modified
        wchar_t const** argv = dummy_args;
        int argc = sizeof(dummy_args) / sizeof(dummy_args[0]) - 1;
 
#if PY_MAJOR_VERSION >= 3
        PySys_SetArgv(argc, const_cast<wchar_t**>(argv));
#else
        PySys_SetArgv(argc, (char**)(argv));
#endif
 
#ifndef WITHOUT_NUMPY
        import_numpy(); // initialize numpy C-API
#endif
 
        PyObject* matplotlibname = PyString_FromString("matplotlib");
        PyObject* pyplotname = PyString_FromString("matplotlib.pyplot");
        PyObject* cmname = PyString_FromString("matplotlib.cm");
        PyObject* pylabname = PyString_FromString("pylab");
        if (!pyplotname || !pylabname || !matplotlibname || !cmname) {
            throw std::runtime_error("couldnt create string");
        }
 
        PyObject* matplotlib = PyImport_Import(matplotlibname);
 
        Py_DECREF(matplotlibname);
        if (!matplotlib) {
            PyErr_Print();
            throw std::runtime_error("Error loading module matplotlib!");
        }
 
        // matplotlib.use() must be called *before* pylab, matplotlib.pyplot,
        // or matplotlib.backends is imported for the first time
        if (!s_backend.empty()) {
            PyObject_CallMethod(matplotlib, const_cast<char*>("use"), const_cast<char*>("s"),
                                s_backend.c_str());
        }
 
        PyObject* pymod = PyImport_Import(pyplotname);
        Py_DECREF(pyplotname);
        if (!pymod) {
            throw std::runtime_error("Error loading module matplotlib.pyplot!");
        }
 
        s_python_colormap = PyImport_Import(cmname);
        Py_DECREF(cmname);
        if (!s_python_colormap) {
            throw std::runtime_error("Error loading module matplotlib.cm!");
        }
 
        PyObject* pylabmod = PyImport_Import(pylabname);
        Py_DECREF(pylabname);
        if (!pylabmod) {
            throw std::runtime_error("Error loading module pylab!");
        }
 
        s_python_function_arrow = safe_import(pymod, "arrow");
        s_python_function_show = safe_import(pymod, "show");
        s_python_function_close = safe_import(pymod, "close");
        s_python_function_draw = safe_import(pymod, "draw");
        s_python_function_pause = safe_import(pymod, "pause");
        s_python_function_figure = safe_import(pymod, "figure");
        s_python_function_fignum_exists = safe_import(pymod, "fignum_exists");
        s_python_function_plot = safe_import(pymod, "plot");
        s_python_function_quiver = safe_import(pymod, "quiver");
        s_python_function_contour = safe_import(pymod, "contour");
        s_python_function_semilogx = safe_import(pymod, "semilogx");
        s_python_function_semilogy = safe_import(pymod, "semilogy");
        s_python_function_loglog = safe_import(pymod, "loglog");
        s_python_function_fill = safe_import(pymod, "fill");
        s_python_function_fill_between = safe_import(pymod, "fill_between");
        s_python_function_hist = safe_import(pymod, "hist");
        s_python_function_scatter = safe_import(pymod, "scatter");
        s_python_function_boxplot = safe_import(pymod, "boxplot");
        s_python_function_subplot = safe_import(pymod, "subplot");
        s_python_function_subplot2grid = safe_import(pymod, "subplot2grid");
        s_python_function_legend = safe_import(pymod, "legend");
        s_python_function_xlim = safe_import(pymod, "xlim");
        s_python_function_ylim = safe_import(pymod, "ylim");
        s_python_function_title = safe_import(pymod, "title");
        s_python_function_axis = safe_import(pymod, "axis");
        s_python_function_axhline = safe_import(pymod, "axhline");
        s_python_function_axvline = safe_import(pymod, "axvline");
        s_python_function_axvspan = safe_import(pymod, "axvspan");
        s_python_function_xlabel = safe_import(pymod, "xlabel");
        s_python_function_ylabel = safe_import(pymod, "ylabel");
        s_python_function_gca = safe_import(pymod, "gca");
        s_python_function_xticks = safe_import(pymod, "xticks");
        s_python_function_yticks = safe_import(pymod, "yticks");
        s_python_function_margins = safe_import(pymod, "margins");
        s_python_function_tick_params = safe_import(pymod, "tick_params");
        s_python_function_grid = safe_import(pymod, "grid");
        s_python_function_ion = safe_import(pymod, "ion");
        s_python_function_ginput = safe_import(pymod, "ginput");
        s_python_function_save = safe_import(pylabmod, "savefig");
        s_python_function_annotate = safe_import(pymod, "annotate");
        s_python_function_cla = safe_import(pymod, "cla");
        s_python_function_clf = safe_import(pymod, "clf");
        s_python_function_errorbar = safe_import(pymod, "errorbar");
        s_python_function_tight_layout = safe_import(pymod, "tight_layout");
        s_python_function_stem = safe_import(pymod, "stem");
        s_python_function_xkcd = safe_import(pymod, "xkcd");
        s_python_function_text = safe_import(pymod, "text");
        s_python_function_suptitle = safe_import(pymod, "suptitle");
        s_python_function_bar = safe_import(pymod, "bar");
        s_python_function_barh = safe_import(pymod, "barh");
        s_python_function_colorbar = PyObject_GetAttrString(pymod, "colorbar");
        s_python_function_subplots_adjust = safe_import(pymod, "subplots_adjust");
        s_python_function_rcparams = PyObject_GetAttrString(pymod, "rcParams");
        s_python_function_spy = PyObject_GetAttrString(pymod, "spy");
#ifndef WITHOUT_NUMPY
        s_python_function_imshow = safe_import(pymod, "imshow");
#endif
        s_python_empty_tuple = PyTuple_New(0);
    }
 
    ~_interpreter() { Py_Finalize(); }
};
 
} // end namespace detail

inline void backend(const std::string& name) {
    detail::s_backend = name;
}
 
inline bool annotate(std::string annotation, double x, double y) {
    detail::_interpreter::get();
 
    PyObject* xy = PyTuple_New(2);
    PyObject* str = PyString_FromString(annotation.c_str());
 
    PyTuple_SetItem(xy, 0, PyFloat_FromDouble(x));
    PyTuple_SetItem(xy, 1, PyFloat_FromDouble(y));
 
    PyObject* kwargs = PyDict_New();
    PyDict_SetItemString(kwargs, "xy", xy);
 
    PyObject* args = PyTuple_New(1);
    PyTuple_SetItem(args, 0, str);
 
    PyObject* res =
        PyObject_Call(detail::_interpreter::get().s_python_function_annotate, args, kwargs);
 
    Py_DECREF(args);
    Py_DECREF(kwargs);
 
    if (res)
        Py_DECREF(res);
 
    return res;
}
 
namespace detail {
 
#ifndef WITHOUT_NUMPY
// Type selector for numpy array conversion
template <typename T> struct select_npy_type {
    const static NPY_TYPES type = NPY_NOTYPE;
}; // Default
template <> struct select_npy_type<double> {
    const static NPY_TYPES type = NPY_DOUBLE;
};
template <> struct select_npy_type<float> {
    const static NPY_TYPES type = NPY_FLOAT;
};
template <> struct select_npy_type<bool> {
    const static NPY_TYPES type = NPY_BOOL;
};
template <> struct select_npy_type<int8_t> {
    const static NPY_TYPES type = NPY_INT8;
};
template <> struct select_npy_type<int16_t> {
    const static NPY_TYPES type = NPY_SHORT;
};
template <> struct select_npy_type<int32_t> {
    const static NPY_TYPES type = NPY_INT;
};
template <> struct select_npy_type<int64_t> {
    const static NPY_TYPES type = NPY_INT64;
};
template <> struct select_npy_type<uint8_t> {
    const static NPY_TYPES type = NPY_UINT8;
};
template <> struct select_npy_type<uint16_t> {
    const static NPY_TYPES type = NPY_USHORT;
};
template <> struct select_npy_type<uint32_t> {
    const static NPY_TYPES type = NPY_ULONG;
};
template <> struct select_npy_type<uint64_t> {
    const static NPY_TYPES type = NPY_UINT64;
};
 
// Sanity checks; comment them out or change the numpy type below if you're
// compiling on a platform where they don't apply
static_assert(sizeof(long long) == 8);
template <> struct select_npy_type<long long> {
    const static NPY_TYPES type = NPY_INT64;
};
static_assert(sizeof(unsigned long long) == 8);
template <> struct select_npy_type<unsigned long long> {
    const static NPY_TYPES type = NPY_UINT64;
};
 
template <typename Numeric> PyObject* get_array(const std::vector<Numeric>& v) {
    npy_intp vsize = v.size();
    NPY_TYPES type = select_npy_type<Numeric>::type;
    if (type == NPY_NOTYPE) {
        size_t memsize = v.size() * sizeof(double);
        double* dp = static_cast<double*>(::malloc(memsize));
        for (size_t i = 0; i < v.size(); ++i)
            dp[i] = v[i];
        PyObject* varray = PyArray_SimpleNewFromData(1, &vsize, NPY_DOUBLE, dp);
        PyArray_UpdateFlags(reinterpret_cast<PyArrayObject*>(varray), NPY_ARRAY_OWNDATA);
        return varray;
    }
 
    PyObject* varray = PyArray_SimpleNewFromData(1, &vsize, type, (void*)(v.data()));
    return varray;
}
 
template <typename Numeric> PyObject* get_2darray(const std::vector<::std::vector<Numeric>>& v) {
    if (v.size() < 1)
        throw std::runtime_error("get_2d_array v too small");
 
    npy_intp vsize[2] = {static_cast<npy_intp>(v.size()), static_cast<npy_intp>(v[0].size())};
 
    PyArrayObject* varray = (PyArrayObject*)PyArray_SimpleNew(2, vsize, NPY_DOUBLE);
 
    double* vd_begin = static_cast<double*>(PyArray_DATA(varray));
 
    for (const ::std::vector<Numeric>& v_row : v) {
        if (v_row.size() != static_cast<size_t>(vsize[1]))
            throw std::runtime_error("Missmatched array size");
        std::copy(v_row.begin(), v_row.end(), vd_begin);
        vd_begin += vsize[1];
    }
 
    return reinterpret_cast<PyObject*>(varray);
}
 
#else // fallback if we don't have numpy: copy every element of the given vector
 
template <typename Numeric> PyObject* get_array(const std::vector<Numeric>& v) {
    PyObject* list = PyList_New(v.size());
    for (size_t i = 0; i < v.size(); ++i) {
        PyList_SetItem(list, i, PyFloat_FromDouble(v.at(i)));
    }
    return list;
}
 
#endif // WITHOUT_NUMPY
 
// sometimes, for labels and such, we need string arrays
inline PyObject* get_array(const std::vector<std::string>& strings) {
    PyObject* list = PyList_New(strings.size());
    for (std::size_t i = 0; i < strings.size(); ++i) {
        PyList_SetItem(list, i, PyString_FromString(strings[i].c_str()));
    }
    return list;
}
 
// not all matplotlib need 2d arrays, some prefer lists of lists
template <typename Numeric> PyObject* get_listlist(const std::vector<std::vector<Numeric>>& ll) {
    PyObject* listlist = PyList_New(ll.size());
    for (std::size_t i = 0; i < ll.size(); ++i) {
        PyList_SetItem(listlist, i, get_array(ll[i]));
    }
    return listlist;
}
 
} // namespace detail

template <typename Numeric>
bool plot(const std::vector<Numeric>& x, const std::vector<Numeric>& y,
          const std::map<std::string, std::string>& keywords) {
    assert(x.size() == y.size());
 
    detail::_interpreter::get();
 
    // using numpy arrays
    PyObject* xarray = detail::get_array(x);
    PyObject* yarray = detail::get_array(y);
 
    // construct positional args
    PyObject* args = PyTuple_New(2);
    PyTuple_SetItem(args, 0, xarray);
    PyTuple_SetItem(args, 1, yarray);
 
    // construct keyword args
    PyObject* kwargs = PyDict_New();
    for (std::map<std::string, std::string>::const_iterator it = keywords.begin();
         it != keywords.end(); ++it) {
        PyDict_SetItemString(kwargs, it->first.c_str(), PyString_FromString(it->second.c_str()));
    }
 
    PyObject* res = PyObject_Call(detail::_interpreter::get().s_python_function_plot, args, kwargs);
 
    Py_DECREF(args);
    Py_DECREF(kwargs);
    if (res)
        Py_DECREF(res);
 
    return res;
}
 
// TODO - it should be possible to make this work by implementing
// a non-numpy alternative for `detail::get_2darray()`.
#ifndef WITHOUT_NUMPY
template <typename Numeric>
void plot_surface(
    const std::vector<::std::vector<Numeric>>& x, const std::vector<::std::vector<Numeric>>& y,
    const std::vector<::std::vector<Numeric>>& z,
    const std::map<std::string, std::string>& keywords = std::map<std::string, std::string>(),
    const long fig_number = 0) {
    detail::_interpreter::get();
 
    // We lazily load the modules here the first time this function is called
    // because I'm not sure that we can assume "matplotlib installed" implies
    // "mpl_toolkits installed" on all platforms, and we don't want to require
    // it for people who don't need 3d plots.
    static PyObject *mpl_toolkitsmod = nullptr, *axis3dmod = nullptr;
    if (!mpl_toolkitsmod) {
        detail::_interpreter::get();
 
        PyObject* mpl_toolkits = PyString_FromString("mpl_toolkits");
        PyObject* axis3d = PyString_FromString("mpl_toolkits.mplot3d");
        if (!mpl_toolkits || !axis3d) {
            throw std::runtime_error("couldnt create string");
        }
 
        mpl_toolkitsmod = PyImport_Import(mpl_toolkits);
        Py_DECREF(mpl_toolkits);
        if (!mpl_toolkitsmod) {
            throw std::runtime_error("Error loading module mpl_toolkits!");
        }
 
        axis3dmod = PyImport_Import(axis3d);
        Py_DECREF(axis3d);
        if (!axis3dmod) {
            throw std::runtime_error("Error loading module mpl_toolkits.mplot3d!");
        }
    }
 
    assert(x.size() == y.size());
    assert(y.size() == z.size());
 
    // using numpy arrays
    PyObject* xarray = detail::get_2darray(x);
    PyObject* yarray = detail::get_2darray(y);
    PyObject* zarray = detail::get_2darray(z);
 
    // construct positional args
    PyObject* args = PyTuple_New(3);
    PyTuple_SetItem(args, 0, xarray);
    PyTuple_SetItem(args, 1, yarray);
    PyTuple_SetItem(args, 2, zarray);
 
    // Build up the kw args.
    PyObject* kwargs = PyDict_New();
    PyDict_SetItemString(kwargs, "rstride", PyInt_FromLong(1));
    PyDict_SetItemString(kwargs, "cstride", PyInt_FromLong(1));
 
    PyObject* python_colormap_coolwarm =
        PyObject_GetAttrString(detail::_interpreter::get().s_python_colormap, "coolwarm");
 
    PyDict_SetItemString(kwargs, "cmap", python_colormap_coolwarm);
 
    for (std::map<std::string, std::string>::const_iterator it = keywords.begin();
         it != keywords.end(); ++it) {
        if (it->first == "linewidth" || it->first == "alpha") {
            PyDict_SetItemString(kwargs, it->first.c_str(),
                                 PyFloat_FromDouble(std::stod(it->second)));
        } else {
            PyDict_SetItemString(kwargs, it->first.c_str(),
                                 PyString_FromString(it->second.c_str()));
        }
    }
 
    PyObject* fig_args = PyTuple_New(1);
    PyObject* fig = nullptr;
    PyTuple_SetItem(fig_args, 0, PyLong_FromLong(fig_number));
    PyObject* fig_exists =
        PyObject_CallObject(detail::_interpreter::get().s_python_function_fignum_exists, fig_args);
    if (!PyObject_IsTrue(fig_exists)) {
        fig = PyObject_CallObject(detail::_interpreter::get().s_python_function_figure,
                                  detail::_interpreter::get().s_python_empty_tuple);
    } else {
        fig = PyObject_CallObject(detail::_interpreter::get().s_python_function_figure, fig_args);
    }
    Py_DECREF(fig_exists);
    if (!fig)
        throw std::runtime_error("Call to figure() failed.");
 
    PyObject* gca_kwargs = PyDict_New();
    PyDict_SetItemString(gca_kwargs, "projection", PyString_FromString("3d"));
 
    PyObject* gca = PyObject_GetAttrString(fig, "gca");
    if (!gca)
        throw std::runtime_error("No gca");
    Py_INCREF(gca);
    PyObject* axis =
        PyObject_Call(gca, detail::_interpreter::get().s_python_empty_tuple, gca_kwargs);
 
    if (!axis)
        throw std::runtime_error("No axis");
    Py_INCREF(axis);
 
    Py_DECREF(gca);
    Py_DECREF(gca_kwargs);
 
    PyObject* plot_surface = PyObject_GetAttrString(axis, "plot_surface");
    if (!plot_surface)
        throw std::runtime_error("No surface");
    Py_INCREF(plot_surface);
    PyObject* res = PyObject_Call(plot_surface, args, kwargs);
    if (!res)
        throw std::runtime_error("failed surface");
    Py_DECREF(plot_surface);
 
    Py_DECREF(axis);
    Py_DECREF(args);
    Py_DECREF(kwargs);
    if (res)
        Py_DECREF(res);
}
 
template <typename Numeric>
void contour(const std::vector<::std::vector<Numeric>>& x,
             const std::vector<::std::vector<Numeric>>& y,
             const std::vector<::std::vector<Numeric>>& z,
             const std::map<std::string, std::string>& keywords = {}) {
    detail::_interpreter::get();
 
    // using numpy arrays
    PyObject* xarray = detail::get_2darray(x);
    PyObject* yarray = detail::get_2darray(y);
    PyObject* zarray = detail::get_2darray(z);
 
    // construct positional args
    PyObject* args = PyTuple_New(3);
    PyTuple_SetItem(args, 0, xarray);
    PyTuple_SetItem(args, 1, yarray);
    PyTuple_SetItem(args, 2, zarray);
 
    // Build up the kw args.
    PyObject* kwargs = PyDict_New();
 
    PyObject* python_colormap_coolwarm =
        PyObject_GetAttrString(detail::_interpreter::get().s_python_colormap, "coolwarm");
 
    PyDict_SetItemString(kwargs, "cmap", python_colormap_coolwarm);
 
    for (std::map<std::string, std::string>::const_iterator it = keywords.begin();
         it != keywords.end(); ++it) {
        PyDict_SetItemString(kwargs, it->first.c_str(), PyString_FromString(it->second.c_str()));
    }
 
    PyObject* res =
        PyObject_Call(detail::_interpreter::get().s_python_function_contour, args, kwargs);
    if (!res)
        throw std::runtime_error("failed contour");
 
    Py_DECREF(args);
    Py_DECREF(kwargs);
    if (res)
        Py_DECREF(res);
}
 
template <typename Numeric>
void spy(const std::vector<::std::vector<Numeric>>& x,
         const double markersize = -1, // -1 for default matplotlib size
         const std::map<std::string, std::string>& keywords = {}) {
    detail::_interpreter::get();
 
    PyObject* xarray = detail::get_2darray(x);
 
    PyObject* kwargs = PyDict_New();
    if (markersize != -1) {
        PyDict_SetItemString(kwargs, "markersize", PyFloat_FromDouble(markersize));
    }
    for (std::map<std::string, std::string>::const_iterator it = keywords.begin();
         it != keywords.end(); ++it) {
        PyDict_SetItemString(kwargs, it->first.c_str(), PyString_FromString(it->second.c_str()));
    }
 
    PyObject* plot_args = PyTuple_New(1);
    PyTuple_SetItem(plot_args, 0, xarray);
 
    PyObject* res =
        PyObject_Call(detail::_interpreter::get().s_python_function_spy, plot_args, kwargs);
 
    Py_DECREF(plot_args);
    Py_DECREF(kwargs);
    if (res)
        Py_DECREF(res);
}
#endif // WITHOUT_NUMPY
 
template <typename Numeric>
void plot3(
    const std::vector<Numeric>& x, const std::vector<Numeric>& y, const std::vector<Numeric>& z,
    const std::map<std::string, std::string>& keywords = std::map<std::string, std::string>(),
    const long fig_number = 0) {
    detail::_interpreter::get();
 
    // Same as with plot_surface: We lazily load the modules here the first time
    // this function is called because I'm not sure that we can assume "matplotlib
    // installed" implies "mpl_toolkits installed" on all platforms, and we don't
    // want to require it for people who don't need 3d plots.
    static PyObject *mpl_toolkitsmod = nullptr, *axis3dmod = nullptr;
    if (!mpl_toolkitsmod) {
        detail::_interpreter::get();
 
        PyObject* mpl_toolkits = PyString_FromString("mpl_toolkits");
        PyObject* axis3d = PyString_FromString("mpl_toolkits.mplot3d");
        if (!mpl_toolkits || !axis3d) {
            throw std::runtime_error("couldnt create string");
        }
 
        mpl_toolkitsmod = PyImport_Import(mpl_toolkits);
        Py_DECREF(mpl_toolkits);
        if (!mpl_toolkitsmod) {
            throw std::runtime_error("Error loading module mpl_toolkits!");
        }
 
        axis3dmod = PyImport_Import(axis3d);
        Py_DECREF(axis3d);
        if (!axis3dmod) {
            throw std::runtime_error("Error loading module mpl_toolkits.mplot3d!");
        }
    }
 
    assert(x.size() == y.size());
    assert(y.size() == z.size());
 
    PyObject* xarray = detail::get_array(x);
    PyObject* yarray = detail::get_array(y);
    PyObject* zarray = detail::get_array(z);
 
    // construct positional args
    PyObject* args = PyTuple_New(3);
    PyTuple_SetItem(args, 0, xarray);
    PyTuple_SetItem(args, 1, yarray);
    PyTuple_SetItem(args, 2, zarray);
 
    // Build up the kw args.
    PyObject* kwargs = PyDict_New();
 
    for (std::map<std::string, std::string>::const_iterator it = keywords.begin();
         it != keywords.end(); ++it) {
        PyDict_SetItemString(kwargs, it->first.c_str(), PyString_FromString(it->second.c_str()));
    }
 
    PyObject* fig_args = PyTuple_New(1);
    PyObject* fig = nullptr;
    PyTuple_SetItem(fig_args, 0, PyLong_FromLong(fig_number));
    PyObject* fig_exists =
        PyObject_CallObject(detail::_interpreter::get().s_python_function_fignum_exists, fig_args);
    if (!PyObject_IsTrue(fig_exists)) {
        fig = PyObject_CallObject(detail::_interpreter::get().s_python_function_figure,
                                  detail::_interpreter::get().s_python_empty_tuple);
    } else {
        fig = PyObject_CallObject(detail::_interpreter::get().s_python_function_figure, fig_args);
    }
    if (!fig)
        throw std::runtime_error("Call to figure() failed.");
 
    PyObject* gca_kwargs = PyDict_New();
    PyDict_SetItemString(gca_kwargs, "projection", PyString_FromString("3d"));
 
    PyObject* gca = PyObject_GetAttrString(fig, "gca");
    if (!gca)
        throw std::runtime_error("No gca");
    Py_INCREF(gca);
    PyObject* axis =
        PyObject_Call(gca, detail::_interpreter::get().s_python_empty_tuple, gca_kwargs);
 
    if (!axis)
        throw std::runtime_error("No axis");
    Py_INCREF(axis);
 
    Py_DECREF(gca);
    Py_DECREF(gca_kwargs);
 
    PyObject* plot3 = PyObject_GetAttrString(axis, "plot");
    if (!plot3)
        throw std::runtime_error("No 3D line plot");
    Py_INCREF(plot3);
    PyObject* res = PyObject_Call(plot3, args, kwargs);
    if (!res)
        throw std::runtime_error("Failed 3D line plot");
    Py_DECREF(plot3);
 
    Py_DECREF(axis);
    Py_DECREF(args);
    Py_DECREF(kwargs);
    if (res)
        Py_DECREF(res);
}
 
template <typename Numeric>
bool stem(const std::vector<Numeric>& x, const std::vector<Numeric>& y,
          const std::map<std::string, std::string>& keywords) {
    assert(x.size() == y.size());
 
    detail::_interpreter::get();
 
    // using numpy arrays
    PyObject* xarray = detail::get_array(x);
    PyObject* yarray = detail::get_array(y);
 
    // construct positional args
    PyObject* args = PyTuple_New(2);
    PyTuple_SetItem(args, 0, xarray);
    PyTuple_SetItem(args, 1, yarray);
 
    // construct keyword args
    PyObject* kwargs = PyDict_New();
    for (std::map<std::string, std::string>::const_iterator it = keywords.begin();
         it != keywords.end(); ++it) {
        PyDict_SetItemString(kwargs, it->first.c_str(), PyString_FromString(it->second.c_str()));
    }
 
    PyObject* res = PyObject_Call(detail::_interpreter::get().s_python_function_stem, args, kwargs);
 
    Py_DECREF(args);
    Py_DECREF(kwargs);
    if (res)
        Py_DECREF(res);
 
    return res;
}
 
template <typename Numeric>
bool fill(const std::vector<Numeric>& x, const std::vector<Numeric>& y,
          const std::map<std::string, std::string>& keywords) {
    assert(x.size() == y.size());
 
    detail::_interpreter::get();
 
    // using numpy arrays
    PyObject* xarray = detail::get_array(x);
    PyObject* yarray = detail::get_array(y);
 
    // construct positional args
    PyObject* args = PyTuple_New(2);
    PyTuple_SetItem(args, 0, xarray);
    PyTuple_SetItem(args, 1, yarray);
 
    // construct keyword args
    PyObject* kwargs = PyDict_New();
    for (auto it = keywords.begin(); it != keywords.end(); ++it) {
        PyDict_SetItemString(kwargs, it->first.c_str(), PyUnicode_FromString(it->second.c_str()));
    }
 
    PyObject* res = PyObject_Call(detail::_interpreter::get().s_python_function_fill, args, kwargs);
 
    Py_DECREF(args);
    Py_DECREF(kwargs);
 
    if (res)
        Py_DECREF(res);
 
    return res;
}
 
template <typename Numeric>
bool fill_between(const std::vector<Numeric>& x, const std::vector<Numeric>& y1,
                  const std::vector<Numeric>& y2,
                  const std::map<std::string, std::string>& keywords) {
    assert(x.size() == y1.size());
    assert(x.size() == y2.size());
 
    detail::_interpreter::get();
 
    // using numpy arrays
    PyObject* xarray = detail::get_array(x);
    PyObject* y1array = detail::get_array(y1);
    PyObject* y2array = detail::get_array(y2);
 
    // construct positional args
    PyObject* args = PyTuple_New(3);
    PyTuple_SetItem(args, 0, xarray);
    PyTuple_SetItem(args, 1, y1array);
    PyTuple_SetItem(args, 2, y2array);
 
    // construct keyword args
    PyObject* kwargs = PyDict_New();
    for (std::map<std::string, std::string>::const_iterator it = keywords.begin();
         it != keywords.end(); ++it) {
        PyDict_SetItemString(kwargs, it->first.c_str(), PyUnicode_FromString(it->second.c_str()));
    }
 
    PyObject* res =
        PyObject_Call(detail::_interpreter::get().s_python_function_fill_between, args, kwargs);
 
    Py_DECREF(args);
    Py_DECREF(kwargs);
    if (res)
        Py_DECREF(res);
 
    return res;
}
 
template <typename Numeric>
bool arrow(Numeric x, Numeric y, Numeric end_x, Numeric end_y, const std::string& fc = "r",
           const std::string ec = "k", Numeric head_length = 0.25, Numeric head_width = 0.1625) {
    PyObject* obj_x = PyFloat_FromDouble(x);
    PyObject* obj_y = PyFloat_FromDouble(y);
    PyObject* obj_end_x = PyFloat_FromDouble(end_x);
    PyObject* obj_end_y = PyFloat_FromDouble(end_y);
 
    PyObject* kwargs = PyDict_New();
    PyDict_SetItemString(kwargs, "fc", PyString_FromString(fc.c_str()));
    PyDict_SetItemString(kwargs, "ec", PyString_FromString(ec.c_str()));
    PyDict_SetItemString(kwargs, "head_width", PyFloat_FromDouble(head_width));
    PyDict_SetItemString(kwargs, "head_length", PyFloat_FromDouble(head_length));
 
    PyObject* plot_args = PyTuple_New(4);
    PyTuple_SetItem(plot_args, 0, obj_x);
    PyTuple_SetItem(plot_args, 1, obj_y);
    PyTuple_SetItem(plot_args, 2, obj_end_x);
    PyTuple_SetItem(plot_args, 3, obj_end_y);
 
    PyObject* res =
        PyObject_Call(detail::_interpreter::get().s_python_function_arrow, plot_args, kwargs);
 
    Py_DECREF(plot_args);
    Py_DECREF(kwargs);
    if (res)
        Py_DECREF(res);
 
    return res;
}
 
template <typename Numeric>
bool hist(const std::vector<Numeric>& y, long bins = 10, std::string color = "b",
          double alpha = 1.0, bool cumulative = false) {
    detail::_interpreter::get();
 
    PyObject* yarray = detail::get_array(y);
 
    PyObject* kwargs = PyDict_New();
    PyDict_SetItemString(kwargs, "bins", PyLong_FromLong(bins));
    PyDict_SetItemString(kwargs, "color", PyString_FromString(color.c_str()));
    PyDict_SetItemString(kwargs, "alpha", PyFloat_FromDouble(alpha));
    PyDict_SetItemString(kwargs, "cumulative", cumulative ? Py_True : Py_False);
 
    PyObject* plot_args = PyTuple_New(1);
 
    PyTuple_SetItem(plot_args, 0, yarray);
 
    PyObject* res =
        PyObject_Call(detail::_interpreter::get().s_python_function_hist, plot_args, kwargs);
 
    Py_DECREF(plot_args);
    Py_DECREF(kwargs);
    if (res)
        Py_DECREF(res);
 
    return res;
}
 
#ifndef WITHOUT_NUMPY
namespace detail {
 
inline void imshow(void* ptr, const NPY_TYPES type, const int rows, const int columns,
                   const int colors, const std::map<std::string, std::string>& keywords,
                   PyObject** out) {
    assert(type == NPY_UINT8 || type == NPY_FLOAT);
    assert(colors == 1 || colors == 3 || colors == 4);
 
    detail::_interpreter::get();
 
    // construct args
    npy_intp dims[3] = {rows, columns, colors};
    PyObject* args = PyTuple_New(1);
    PyTuple_SetItem(args, 0, PyArray_SimpleNewFromData(colors == 1 ? 2 : 3, dims, type, ptr));
 
    // construct keyword args
    PyObject* kwargs = PyDict_New();
    for (std::map<std::string, std::string>::const_iterator it = keywords.begin();
         it != keywords.end(); ++it) {
        PyDict_SetItemString(kwargs, it->first.c_str(), PyUnicode_FromString(it->second.c_str()));
    }
 
    PyObject* res =
        PyObject_Call(detail::_interpreter::get().s_python_function_imshow, args, kwargs);
    Py_DECREF(args);
    Py_DECREF(kwargs);
    if (!res)
        throw std::runtime_error("Call to imshow() failed");
    if (out)
        *out = res;
    else
        Py_DECREF(res);
}
 
} // namespace detail
 
inline void imshow(const unsigned char* ptr, const int rows, const int columns, const int colors,
                   const std::map<std::string, std::string>& keywords = {},
                   PyObject** out = nullptr) {
    detail::imshow((void*)ptr, NPY_UINT8, rows, columns, colors, keywords, out);
}
 
inline void imshow(const float* ptr, const int rows, const int columns, const int colors,
                   const std::map<std::string, std::string>& keywords = {},
                   PyObject** out = nullptr) {
    detail::imshow((void*)ptr, NPY_FLOAT, rows, columns, colors, keywords, out);
}
 
#ifdef WITH_OPENCV
void imshow(const cv::Mat& image, const std::map<std::string, std::string>& keywords = {}) {
    // Convert underlying type of matrix, if needed
    cv::Mat image2;
    NPY_TYPES npy_type = NPY_UINT8;
    switch (image.type() & CV_MAT_DEPTH_MASK) {
        case CV_8U:
            image2 = image;
            break;
        case CV_32F:
            image2 = image;
            npy_type = NPY_FLOAT;
            break;
        default:
            image.convertTo(image2, CV_MAKETYPE(CV_8U, image.channels()));
    }
 
    // If color image, convert from BGR to RGB
    switch (image2.channels()) {
        case 3:
            cv::cvtColor(image2, image2, CV_BGR2RGB);
            break;
        case 4:
            cv::cvtColor(image2, image2, CV_BGRA2RGBA);
    }
 
    detail::imshow(image2.data, npy_type, image2.rows, image2.cols, image2.channels(), keywords);
}
#endif // WITH_OPENCV
#endif // WITHOUT_NUMPY
 
template <typename NumericX, typename NumericY>
bool scatter(const std::vector<NumericX>& x, const std::vector<NumericY>& y,
             const double s = 1.0, // The marker size in points**2
             const std::map<std::string, std::string>& keywords = {}) {
    detail::_interpreter::get();
 
    assert(x.size() == y.size());
 
    PyObject* xarray = detail::get_array(x);
    PyObject* yarray = detail::get_array(y);
 
    PyObject* kwargs = PyDict_New();
    PyDict_SetItemString(kwargs, "s", PyLong_FromLong(s));
    for (const auto& it : keywords) {
        PyDict_SetItemString(kwargs, it.first.c_str(), PyString_FromString(it.second.c_str()));
    }
 
    PyObject* plot_args = PyTuple_New(2);
    PyTuple_SetItem(plot_args, 0, xarray);
    PyTuple_SetItem(plot_args, 1, yarray);
 
    PyObject* res =
        PyObject_Call(detail::_interpreter::get().s_python_function_scatter, plot_args, kwargs);
 
    Py_DECREF(plot_args);
    Py_DECREF(kwargs);
    if (res)
        Py_DECREF(res);
 
    return res;
}
 
template <typename NumericX, typename NumericY, typename NumericColors>
bool scatter_colored(const std::vector<NumericX>& x, const std::vector<NumericY>& y,
                     const std::vector<NumericColors>& colors,
                     const double s = 1.0, // The marker size in points**2
                     const std::map<std::string, std::string>& keywords = {}) {
    detail::_interpreter::get();
 
    assert(x.size() == y.size());
 
    PyObject* xarray = detail::get_array(x);
    PyObject* yarray = detail::get_array(y);
    PyObject* colors_array = detail::get_array(colors);
 
    PyObject* kwargs = PyDict_New();
    PyDict_SetItemString(kwargs, "s", PyLong_FromLong(s));
    PyDict_SetItemString(kwargs, "c", colors_array);
 
    for (const auto& it : keywords) {
        PyDict_SetItemString(kwargs, it.first.c_str(), PyString_FromString(it.second.c_str()));
    }
 
    PyObject* plot_args = PyTuple_New(2);
    PyTuple_SetItem(plot_args, 0, xarray);
    PyTuple_SetItem(plot_args, 1, yarray);
 
    PyObject* res =
        PyObject_Call(detail::_interpreter::get().s_python_function_scatter, plot_args, kwargs);
 
    Py_DECREF(plot_args);
    Py_DECREF(kwargs);
    if (res)
        Py_DECREF(res);
 
    return res;
}
 
template <typename NumericX, typename NumericY, typename NumericZ>
bool scatter(const std::vector<NumericX>& x, const std::vector<NumericY>& y,
             const std::vector<NumericZ>& z,
             const double s = 1.0, // The marker size in points**2
             const std::map<std::string, std::string>& keywords = {}, const long fig_number = 0) {
    detail::_interpreter::get();
 
    // Same as with plot_surface: We lazily load the modules here the first time
    // this function is called because I'm not sure that we can assume "matplotlib
    // installed" implies "mpl_toolkits installed" on all platforms, and we don't
    // want to require it for people who don't need 3d plots.
    static PyObject *mpl_toolkitsmod = nullptr, *axis3dmod = nullptr;
    if (!mpl_toolkitsmod) {
        detail::_interpreter::get();
 
        PyObject* mpl_toolkits = PyString_FromString("mpl_toolkits");
        PyObject* axis3d = PyString_FromString("mpl_toolkits.mplot3d");
        if (!mpl_toolkits || !axis3d) {
            throw std::runtime_error("couldnt create string");
        }
 
        mpl_toolkitsmod = PyImport_Import(mpl_toolkits);
        Py_DECREF(mpl_toolkits);
        if (!mpl_toolkitsmod) {
            throw std::runtime_error("Error loading module mpl_toolkits!");
        }
 
        axis3dmod = PyImport_Import(axis3d);
        Py_DECREF(axis3d);
        if (!axis3dmod) {
            throw std::runtime_error("Error loading module mpl_toolkits.mplot3d!");
        }
    }
 
    assert(x.size() == y.size());
    assert(y.size() == z.size());
 
    PyObject* xarray = detail::get_array(x);
    PyObject* yarray = detail::get_array(y);
    PyObject* zarray = detail::get_array(z);
 
    // construct positional args
    PyObject* args = PyTuple_New(3);
    PyTuple_SetItem(args, 0, xarray);
    PyTuple_SetItem(args, 1, yarray);
    PyTuple_SetItem(args, 2, zarray);
 
    // Build up the kw args.
    PyObject* kwargs = PyDict_New();
 
    for (std::map<std::string, std::string>::const_iterator it = keywords.begin();
         it != keywords.end(); ++it) {
        PyDict_SetItemString(kwargs, it->first.c_str(), PyString_FromString(it->second.c_str()));
    }
    PyObject* fig_args = PyTuple_New(1);
    PyObject* fig = nullptr;
    PyTuple_SetItem(fig_args, 0, PyLong_FromLong(fig_number));
    PyObject* fig_exists =
        PyObject_CallObject(detail::_interpreter::get().s_python_function_fignum_exists, fig_args);
    if (!PyObject_IsTrue(fig_exists)) {
        fig = PyObject_CallObject(detail::_interpreter::get().s_python_function_figure,
                                  detail::_interpreter::get().s_python_empty_tuple);
    } else {
        fig = PyObject_CallObject(detail::_interpreter::get().s_python_function_figure, fig_args);
    }
    Py_DECREF(fig_exists);
    if (!fig)
        throw std::runtime_error("Call to figure() failed.");
 
    PyObject* gca_kwargs = PyDict_New();
    PyDict_SetItemString(gca_kwargs, "projection", PyString_FromString("3d"));
 
    PyObject* gca = PyObject_GetAttrString(fig, "gca");
    if (!gca)
        throw std::runtime_error("No gca");
    Py_INCREF(gca);
    PyObject* axis =
        PyObject_Call(gca, detail::_interpreter::get().s_python_empty_tuple, gca_kwargs);
 
    if (!axis)
        throw std::runtime_error("No axis");
    Py_INCREF(axis);
 
    Py_DECREF(gca);
    Py_DECREF(gca_kwargs);
 
    PyObject* plot3 = PyObject_GetAttrString(axis, "scatter");
    if (!plot3)
        throw std::runtime_error("No 3D line plot");
    Py_INCREF(plot3);
    PyObject* res = PyObject_Call(plot3, args, kwargs);
    if (!res)
        throw std::runtime_error("Failed 3D line plot");
    Py_DECREF(plot3);
 
    Py_DECREF(axis);
    Py_DECREF(args);
    Py_DECREF(kwargs);
    Py_DECREF(fig);
    if (res)
        Py_DECREF(res);
    return res;
}
 
template <typename Numeric>
bool boxplot(const std::vector<std::vector<Numeric>>& data,
             const std::vector<std::string>& labels = {},
             const std::map<std::string, std::string>& keywords = {}) {
    detail::_interpreter::get();
 
    PyObject* listlist = detail::get_listlist(data);
    PyObject* args = PyTuple_New(1);
    PyTuple_SetItem(args, 0, listlist);
 
    PyObject* kwargs = PyDict_New();
 
    // kwargs needs the labels, if there are (the correct number of) labels
    if (!labels.empty() && labels.size() == data.size()) {
        PyDict_SetItemString(kwargs, "labels", detail::get_array(labels));
    }
 
    // take care of the remaining keywords
    for (const auto& it : keywords) {
        PyDict_SetItemString(kwargs, it.first.c_str(), PyString_FromString(it.second.c_str()));
    }
 
    PyObject* res =
        PyObject_Call(detail::_interpreter::get().s_python_function_boxplot, args, kwargs);
 
    Py_DECREF(args);
    Py_DECREF(kwargs);
 
    if (res)
        Py_DECREF(res);
 
    return res;
}
 
template <typename Numeric>
bool boxplot(const std::vector<Numeric>& data,
             const std::map<std::string, std::string>& keywords = {}) {
    detail::_interpreter::get();
 
    PyObject* vector = detail::get_array(data);
    PyObject* args = PyTuple_New(1);
    PyTuple_SetItem(args, 0, vector);
 
    PyObject* kwargs = PyDict_New();
    for (const auto& it : keywords) {
        PyDict_SetItemString(kwargs, it.first.c_str(), PyString_FromString(it.second.c_str()));
    }
 
    PyObject* res =
        PyObject_Call(detail::_interpreter::get().s_python_function_boxplot, args, kwargs);
 
    Py_DECREF(args);
    Py_DECREF(kwargs);
 
    if (res)
        Py_DECREF(res);
 
    return res;
}
 
template <typename Numeric>
bool bar(const std::vector<Numeric>& x, const std::vector<Numeric>& y, std::string ec = "black",
         std::string ls = "-", double lw = 1.0,
         const std::map<std::string, std::string>& keywords = {}) {
    detail::_interpreter::get();
 
    PyObject* xarray = detail::get_array(x);
    PyObject* yarray = detail::get_array(y);
 
    PyObject* kwargs = PyDict_New();
 
    PyDict_SetItemString(kwargs, "ec", PyString_FromString(ec.c_str()));
    PyDict_SetItemString(kwargs, "ls", PyString_FromString(ls.c_str()));
    PyDict_SetItemString(kwargs, "lw", PyFloat_FromDouble(lw));
 
    for (std::map<std::string, std::string>::const_iterator it = keywords.begin();
         it != keywords.end(); ++it) {
        PyDict_SetItemString(kwargs, it->first.c_str(), PyUnicode_FromString(it->second.c_str()));
    }
 
    PyObject* plot_args = PyTuple_New(2);
    PyTuple_SetItem(plot_args, 0, xarray);
    PyTuple_SetItem(plot_args, 1, yarray);
 
    PyObject* res =
        PyObject_Call(detail::_interpreter::get().s_python_function_bar, plot_args, kwargs);
 
    Py_DECREF(plot_args);
    Py_DECREF(kwargs);
    if (res)
        Py_DECREF(res);
 
    return res;
}
 
template <typename Numeric>
bool bar(const std::vector<Numeric>& y, std::string ec = "black", std::string ls = "-",
         double lw = 1.0, const std::map<std::string, std::string>& keywords = {}) {
    using T = typename std::remove_reference<decltype(y)>::type::value_type;
 
    detail::_interpreter::get();
 
    std::vector<T> x;
    for (std::size_t i = 0; i < y.size(); i++) {
        x.push_back(i);
    }
 
    return bar(x, y, ec, ls, lw, keywords);
}
 
template <typename Numeric>
bool barh(const std::vector<Numeric>& x, const std::vector<Numeric>& y, std::string ec = "black",
          std::string ls = "-", double lw = 1.0,
          const std::map<std::string, std::string>& keywords = {}) {
    PyObject* xarray = detail::get_array(x);
    PyObject* yarray = detail::get_array(y);
 
    PyObject* kwargs = PyDict_New();
 
    PyDict_SetItemString(kwargs, "ec", PyString_FromString(ec.c_str()));
    PyDict_SetItemString(kwargs, "ls", PyString_FromString(ls.c_str()));
    PyDict_SetItemString(kwargs, "lw", PyFloat_FromDouble(lw));
 
    for (std::map<std::string, std::string>::const_iterator it = keywords.begin();
         it != keywords.end(); ++it) {
        PyDict_SetItemString(kwargs, it->first.c_str(), PyUnicode_FromString(it->second.c_str()));
    }
 
    PyObject* plot_args = PyTuple_New(2);
    PyTuple_SetItem(plot_args, 0, xarray);
    PyTuple_SetItem(plot_args, 1, yarray);
 
    PyObject* res =
        PyObject_Call(detail::_interpreter::get().s_python_function_barh, plot_args, kwargs);
 
    Py_DECREF(plot_args);
    Py_DECREF(kwargs);
    if (res)
        Py_DECREF(res);
 
    return res;
}
 
inline bool subplots_adjust(const std::map<std::string, double>& keywords = {}) {
    detail::_interpreter::get();
 
    PyObject* kwargs = PyDict_New();
    for (std::map<std::string, double>::const_iterator it = keywords.begin(); it != keywords.end();
         ++it) {
        PyDict_SetItemString(kwargs, it->first.c_str(), PyFloat_FromDouble(it->second));
    }
 
    PyObject* plot_args = PyTuple_New(0);
 
    PyObject* res = PyObject_Call(detail::_interpreter::get().s_python_function_subplots_adjust,
                                  plot_args, kwargs);
 
    Py_DECREF(plot_args);
    Py_DECREF(kwargs);
    if (res)
        Py_DECREF(res);
 
    return res;
}
 
template <typename Numeric>
bool named_hist(std::string label, const std::vector<Numeric>& y, long bins = 10,
                std::string color = "b", double alpha = 1.0) {
    detail::_interpreter::get();
 
    PyObject* yarray = detail::get_array(y);
 
    PyObject* kwargs = PyDict_New();
    PyDict_SetItemString(kwargs, "label", PyString_FromString(label.c_str()));
    PyDict_SetItemString(kwargs, "bins", PyLong_FromLong(bins));
    PyDict_SetItemString(kwargs, "color", PyString_FromString(color.c_str()));
    PyDict_SetItemString(kwargs, "alpha", PyFloat_FromDouble(alpha));
 
    PyObject* plot_args = PyTuple_New(1);
    PyTuple_SetItem(plot_args, 0, yarray);
 
    PyObject* res =
        PyObject_Call(detail::_interpreter::get().s_python_function_hist, plot_args, kwargs);
 
    Py_DECREF(plot_args);
    Py_DECREF(kwargs);
    if (res)
        Py_DECREF(res);
 
    return res;
}
 
template <typename NumericX, typename NumericY>
bool plot(const std::vector<NumericX>& x, const std::vector<NumericY>& y,
          const std::string& s = "") {
    assert(x.size() == y.size());
 
    detail::_interpreter::get();
 
    PyObject* xarray = detail::get_array(x);
    PyObject* yarray = detail::get_array(y);
 
    PyObject* pystring = PyString_FromString(s.c_str());
 
    PyObject* plot_args = PyTuple_New(3);
    PyTuple_SetItem(plot_args, 0, xarray);
    PyTuple_SetItem(plot_args, 1, yarray);
    PyTuple_SetItem(plot_args, 2, pystring);
 
    PyObject* res =
        PyObject_CallObject(detail::_interpreter::get().s_python_function_plot, plot_args);
 
    Py_DECREF(plot_args);
    if (res)
        Py_DECREF(res);
 
    return res;
}
 
template <typename NumericX, typename NumericY, typename NumericZ>
bool contour(const std::vector<NumericX>& x, const std::vector<NumericY>& y,
             const std::vector<NumericZ>& z,
             const std::map<std::string, std::string>& keywords = {}) {
    assert(x.size() == y.size() && x.size() == z.size());
 
    PyObject* xarray = detail::get_array(x);
    PyObject* yarray = detail::get_array(y);
    PyObject* zarray = detail::get_array(z);
 
    PyObject* plot_args = PyTuple_New(3);
    PyTuple_SetItem(plot_args, 0, xarray);
    PyTuple_SetItem(plot_args, 1, yarray);
    PyTuple_SetItem(plot_args, 2, zarray);
 
    // construct keyword args
    PyObject* kwargs = PyDict_New();
    for (std::map<std::string, std::string>::const_iterator it = keywords.begin();
         it != keywords.end(); ++it) {
        PyDict_SetItemString(kwargs, it->first.c_str(), PyUnicode_FromString(it->second.c_str()));
    }
 
    PyObject* res =
        PyObject_Call(detail::_interpreter::get().s_python_function_contour, plot_args, kwargs);
 
    Py_DECREF(kwargs);
    Py_DECREF(plot_args);
    if (res)
        Py_DECREF(res);
 
    return res;
}
 
template <typename NumericX, typename NumericY, typename NumericU, typename NumericW>
bool quiver(const std::vector<NumericX>& x, const std::vector<NumericY>& y,
            const std::vector<NumericU>& u, const std::vector<NumericW>& w,
            const std::map<std::string, std::string>& keywords = {}) {
    assert(x.size() == y.size() && x.size() == u.size() && u.size() == w.size());
 
    detail::_interpreter::get();
 
    PyObject* xarray = detail::get_array(x);
    PyObject* yarray = detail::get_array(y);
    PyObject* uarray = detail::get_array(u);
    PyObject* warray = detail::get_array(w);
 
    PyObject* plot_args = PyTuple_New(4);
    PyTuple_SetItem(plot_args, 0, xarray);
    PyTuple_SetItem(plot_args, 1, yarray);
    PyTuple_SetItem(plot_args, 2, uarray);
    PyTuple_SetItem(plot_args, 3, warray);
 
    // construct keyword args
    PyObject* kwargs = PyDict_New();
    for (std::map<std::string, std::string>::const_iterator it = keywords.begin();
         it != keywords.end(); ++it) {
        PyDict_SetItemString(kwargs, it->first.c_str(), PyUnicode_FromString(it->second.c_str()));
    }
 
    PyObject* res =
        PyObject_Call(detail::_interpreter::get().s_python_function_quiver, plot_args, kwargs);
 
    Py_DECREF(kwargs);
    Py_DECREF(plot_args);
    if (res)
        Py_DECREF(res);
 
    return res;
}
 
template <typename NumericX, typename NumericY, typename NumericZ, typename NumericU,
          typename NumericW, typename NumericV>
bool quiver(const std::vector<NumericX>& x, const std::vector<NumericY>& y,
            const std::vector<NumericZ>& z, const std::vector<NumericU>& u,
            const std::vector<NumericW>& w, const std::vector<NumericV>& v,
            const std::map<std::string, std::string>& keywords = {}) {
    // set up 3d axes stuff
    static PyObject *mpl_toolkitsmod = nullptr, *axis3dmod = nullptr;
    if (!mpl_toolkitsmod) {
        detail::_interpreter::get();
 
        PyObject* mpl_toolkits = PyString_FromString("mpl_toolkits");
        PyObject* axis3d = PyString_FromString("mpl_toolkits.mplot3d");
        if (!mpl_toolkits || !axis3d) {
            throw std::runtime_error("couldnt create string");
        }
 
        mpl_toolkitsmod = PyImport_Import(mpl_toolkits);
        Py_DECREF(mpl_toolkits);
        if (!mpl_toolkitsmod) {
            throw std::runtime_error("Error loading module mpl_toolkits!");
        }
 
        axis3dmod = PyImport_Import(axis3d);
        Py_DECREF(axis3d);
        if (!axis3dmod) {
            throw std::runtime_error("Error loading module mpl_toolkits.mplot3d!");
        }
    }
 
    // assert sizes match up
    assert(x.size() == y.size() && x.size() == u.size() && u.size() == w.size() &&
           x.size() == z.size() && x.size() == v.size() && u.size() == v.size());
 
    // set up parameters
    detail::_interpreter::get();
 
    PyObject* xarray = detail::get_array(x);
    PyObject* yarray = detail::get_array(y);
    PyObject* zarray = detail::get_array(z);
    PyObject* uarray = detail::get_array(u);
    PyObject* warray = detail::get_array(w);
    PyObject* varray = detail::get_array(v);
 
    PyObject* plot_args = PyTuple_New(6);
    PyTuple_SetItem(plot_args, 0, xarray);
    PyTuple_SetItem(plot_args, 1, yarray);
    PyTuple_SetItem(plot_args, 2, zarray);
    PyTuple_SetItem(plot_args, 3, uarray);
    PyTuple_SetItem(plot_args, 4, warray);
    PyTuple_SetItem(plot_args, 5, varray);
 
    // construct keyword args
    PyObject* kwargs = PyDict_New();
    for (std::map<std::string, std::string>::const_iterator it = keywords.begin();
         it != keywords.end(); ++it) {
        PyDict_SetItemString(kwargs, it->first.c_str(), PyUnicode_FromString(it->second.c_str()));
    }
 
    // get figure gca to enable 3d projection
    PyObject* fig = PyObject_CallObject(detail::_interpreter::get().s_python_function_figure,
                                        detail::_interpreter::get().s_python_empty_tuple);
    if (!fig)
        throw std::runtime_error("Call to figure() failed.");
 
    PyObject* gca_kwargs = PyDict_New();
    PyDict_SetItemString(gca_kwargs, "projection", PyString_FromString("3d"));
 
    PyObject* gca = PyObject_GetAttrString(fig, "gca");
    if (!gca)
        throw std::runtime_error("No gca");
    Py_INCREF(gca);
    PyObject* axis =
        PyObject_Call(gca, detail::_interpreter::get().s_python_empty_tuple, gca_kwargs);
 
    if (!axis)
        throw std::runtime_error("No axis");
    Py_INCREF(axis);
    Py_DECREF(gca);
    Py_DECREF(gca_kwargs);
 
    // plot our boys bravely, plot them strongly, plot them with a wink and clap
    PyObject* plot3 = PyObject_GetAttrString(axis, "quiver");
    if (!plot3)
        throw std::runtime_error("No 3D line plot");
    Py_INCREF(plot3);
    PyObject* res = PyObject_Call(plot3, plot_args, kwargs);
    if (!res)
        throw std::runtime_error("Failed 3D plot");
    Py_DECREF(plot3);
    Py_DECREF(axis);
    Py_DECREF(kwargs);
    Py_DECREF(plot_args);
    if (res)
        Py_DECREF(res);
 
    return res;
}
 
template <typename NumericX, typename NumericY>
bool stem(const std::vector<NumericX>& x, const std::vector<NumericY>& y,
          const std::string& s = "") {
    assert(x.size() == y.size());
 
    detail::_interpreter::get();
 
    PyObject* xarray = detail::get_array(x);
    PyObject* yarray = detail::get_array(y);
 
    PyObject* pystring = PyString_FromString(s.c_str());
 
    PyObject* plot_args = PyTuple_New(3);
    PyTuple_SetItem(plot_args, 0, xarray);
    PyTuple_SetItem(plot_args, 1, yarray);
    PyTuple_SetItem(plot_args, 2, pystring);
 
    PyObject* res =
        PyObject_CallObject(detail::_interpreter::get().s_python_function_stem, plot_args);
 
    Py_DECREF(plot_args);
    if (res)
        Py_DECREF(res);
 
    return res;
}
 
template <typename NumericX, typename NumericY>
bool semilogx(const std::vector<NumericX>& x, const std::vector<NumericY>& y,
              const std::string& s = "") {
    assert(x.size() == y.size());
 
    detail::_interpreter::get();
 
    PyObject* xarray = detail::get_array(x);
    PyObject* yarray = detail::get_array(y);
 
    PyObject* pystring = PyString_FromString(s.c_str());
 
    PyObject* plot_args = PyTuple_New(3);
    PyTuple_SetItem(plot_args, 0, xarray);
    PyTuple_SetItem(plot_args, 1, yarray);
    PyTuple_SetItem(plot_args, 2, pystring);
 
    PyObject* res =
        PyObject_CallObject(detail::_interpreter::get().s_python_function_semilogx, plot_args);
 
    Py_DECREF(plot_args);
    if (res)
        Py_DECREF(res);
 
    return res;
}
 
template <typename NumericX, typename NumericY>
bool semilogy(const std::vector<NumericX>& x, const std::vector<NumericY>& y,
              const std::string& s = "") {
    assert(x.size() == y.size());
 
    detail::_interpreter::get();
 
    PyObject* xarray = detail::get_array(x);
    PyObject* yarray = detail::get_array(y);
 
    PyObject* pystring = PyString_FromString(s.c_str());
 
    PyObject* plot_args = PyTuple_New(3);
    PyTuple_SetItem(plot_args, 0, xarray);
    PyTuple_SetItem(plot_args, 1, yarray);
    PyTuple_SetItem(plot_args, 2, pystring);
 
    PyObject* res =
        PyObject_CallObject(detail::_interpreter::get().s_python_function_semilogy, plot_args);
 
    Py_DECREF(plot_args);
    if (res)
        Py_DECREF(res);
 
    return res;
}
 
template <typename NumericX, typename NumericY>
bool loglog(const std::vector<NumericX>& x, const std::vector<NumericY>& y,
            const std::string& s = "") {
    assert(x.size() == y.size());
 
    detail::_interpreter::get();
 
    PyObject* xarray = detail::get_array(x);
    PyObject* yarray = detail::get_array(y);
 
    PyObject* pystring = PyString_FromString(s.c_str());
 
    PyObject* plot_args = PyTuple_New(3);
    PyTuple_SetItem(plot_args, 0, xarray);
    PyTuple_SetItem(plot_args, 1, yarray);
    PyTuple_SetItem(plot_args, 2, pystring);
 
    PyObject* res =
        PyObject_CallObject(detail::_interpreter::get().s_python_function_loglog, plot_args);
 
    Py_DECREF(plot_args);
    if (res)
        Py_DECREF(res);
 
    return res;
}
 
template <typename NumericX, typename NumericY>
bool errorbar(const std::vector<NumericX>& x, const std::vector<NumericY>& y,
              const std::vector<NumericX>& yerr,
              const std::map<std::string, std::string>& keywords = {}) {
    assert(x.size() == y.size());
 
    detail::_interpreter::get();
 
    PyObject* xarray = detail::get_array(x);
    PyObject* yarray = detail::get_array(y);
    PyObject* yerrarray = detail::get_array(yerr);
 
    // construct keyword args
    PyObject* kwargs = PyDict_New();
    for (std::map<std::string, std::string>::const_iterator it = keywords.begin();
         it != keywords.end(); ++it) {
        PyDict_SetItemString(kwargs, it->first.c_str(), PyString_FromString(it->second.c_str()));
    }
 
    PyDict_SetItemString(kwargs, "yerr", yerrarray);
 
    PyObject* plot_args = PyTuple_New(2);
    PyTuple_SetItem(plot_args, 0, xarray);
    PyTuple_SetItem(plot_args, 1, yarray);
 
    PyObject* res =
        PyObject_Call(detail::_interpreter::get().s_python_function_errorbar, plot_args, kwargs);
 
    Py_DECREF(kwargs);
    Py_DECREF(plot_args);
 
    if (res)
        Py_DECREF(res);
    else
        throw std::runtime_error("Call to errorbar() failed.");
 
    return res;
}
 
template <typename Numeric>
bool named_plot(const std::string& name, const std::vector<Numeric>& y,
                const std::string& format = "") {
    detail::_interpreter::get();
 
    PyObject* kwargs = PyDict_New();
    PyDict_SetItemString(kwargs, "label", PyString_FromString(name.c_str()));
 
    PyObject* yarray = detail::get_array(y);
 
    PyObject* pystring = PyString_FromString(format.c_str());
 
    PyObject* plot_args = PyTuple_New(2);
 
    PyTuple_SetItem(plot_args, 0, yarray);
    PyTuple_SetItem(plot_args, 1, pystring);
 
    PyObject* res =
        PyObject_Call(detail::_interpreter::get().s_python_function_plot, plot_args, kwargs);
 
    Py_DECREF(kwargs);
    Py_DECREF(plot_args);
    if (res)
        Py_DECREF(res);
 
    return res;
}
 
template <typename NumericX, typename NumericY>
bool named_plot(const std::string& name, const std::vector<NumericX>& x,
                const std::vector<NumericY>& y, const std::string& format = "") {
    detail::_interpreter::get();
 
    PyObject* kwargs = PyDict_New();
    PyDict_SetItemString(kwargs, "label", PyString_FromString(name.c_str()));
 
    PyObject* xarray = detail::get_array(x);
    PyObject* yarray = detail::get_array(y);
 
    PyObject* pystring = PyString_FromString(format.c_str());
 
    PyObject* plot_args = PyTuple_New(3);
    PyTuple_SetItem(plot_args, 0, xarray);
    PyTuple_SetItem(plot_args, 1, yarray);
    PyTuple_SetItem(plot_args, 2, pystring);
 
    PyObject* res =
        PyObject_Call(detail::_interpreter::get().s_python_function_plot, plot_args, kwargs);
 
    Py_DECREF(kwargs);
    Py_DECREF(plot_args);
    if (res)
        Py_DECREF(res);
 
    return res;
}
 
template <typename NumericX, typename NumericY>
bool named_semilogx(const std::string& name, const std::vector<NumericX>& x,
                    const std::vector<NumericY>& y, const std::string& format = "") {
    detail::_interpreter::get();
 
    PyObject* kwargs = PyDict_New();
    PyDict_SetItemString(kwargs, "label", PyString_FromString(name.c_str()));
 
    PyObject* xarray = detail::get_array(x);
    PyObject* yarray = detail::get_array(y);
 
    PyObject* pystring = PyString_FromString(format.c_str());
 
    PyObject* plot_args = PyTuple_New(3);
    PyTuple_SetItem(plot_args, 0, xarray);
    PyTuple_SetItem(plot_args, 1, yarray);
    PyTuple_SetItem(plot_args, 2, pystring);
 
    PyObject* res =
        PyObject_Call(detail::_interpreter::get().s_python_function_semilogx, plot_args, kwargs);
 
    Py_DECREF(kwargs);
    Py_DECREF(plot_args);
    if (res)
        Py_DECREF(res);
 
    return res;
}
 
template <typename NumericX, typename NumericY>
bool named_semilogy(const std::string& name, const std::vector<NumericX>& x,
                    const std::vector<NumericY>& y, const std::string& format = "") {
    detail::_interpreter::get();
 
    PyObject* kwargs = PyDict_New();
    PyDict_SetItemString(kwargs, "label", PyString_FromString(name.c_str()));
 
    PyObject* xarray = detail::get_array(x);
    PyObject* yarray = detail::get_array(y);
 
    PyObject* pystring = PyString_FromString(format.c_str());
 
    PyObject* plot_args = PyTuple_New(3);
    PyTuple_SetItem(plot_args, 0, xarray);
    PyTuple_SetItem(plot_args, 1, yarray);
    PyTuple_SetItem(plot_args, 2, pystring);
 
    PyObject* res =
        PyObject_Call(detail::_interpreter::get().s_python_function_semilogy, plot_args, kwargs);
 
    Py_DECREF(kwargs);
    Py_DECREF(plot_args);
    if (res)
        Py_DECREF(res);
 
    return res;
}
 
template <typename NumericX, typename NumericY>
bool named_loglog(const std::string& name, const std::vector<NumericX>& x,
                  const std::vector<NumericY>& y, const std::string& format = "") {
    detail::_interpreter::get();
 
    PyObject* kwargs = PyDict_New();
    PyDict_SetItemString(kwargs, "label", PyString_FromString(name.c_str()));
 
    PyObject* xarray = detail::get_array(x);
    PyObject* yarray = detail::get_array(y);
 
    PyObject* pystring = PyString_FromString(format.c_str());
 
    PyObject* plot_args = PyTuple_New(3);
    PyTuple_SetItem(plot_args, 0, xarray);
    PyTuple_SetItem(plot_args, 1, yarray);
    PyTuple_SetItem(plot_args, 2, pystring);
    PyObject* res =
        PyObject_Call(detail::_interpreter::get().s_python_function_loglog, plot_args, kwargs);
 
    Py_DECREF(kwargs);
    Py_DECREF(plot_args);
    if (res)
        Py_DECREF(res);
 
    return res;
}
 
template <typename Numeric>
bool plot(const std::vector<Numeric>& y, const std::string& format = "") {
    std::vector<Numeric> x(y.size());
    for (size_t i = 0; i < x.size(); ++i)
        x.at(i) = i;
    return plot(x, y, format);
}
 
template <typename Numeric>
bool plot(const std::vector<Numeric>& y, const std::map<std::string, std::string>& keywords) {
    std::vector<Numeric> x(y.size());
    for (size_t i = 0; i < x.size(); ++i)
        x.at(i) = i;
    return plot(x, y, keywords);
}
 
template <typename Numeric>
bool stem(const std::vector<Numeric>& y, const std::string& format = "") {
    std::vector<Numeric> x(y.size());
    for (size_t i = 0; i < x.size(); ++i)
        x.at(i) = i;
    return stem(x, y, format);
}
 
template <typename Numeric> void text(Numeric x, Numeric y, const std::string& s = "") {
    detail::_interpreter::get();
 
    PyObject* args = PyTuple_New(3);
    PyTuple_SetItem(args, 0, PyFloat_FromDouble(x));
    PyTuple_SetItem(args, 1, PyFloat_FromDouble(y));
    PyTuple_SetItem(args, 2, PyString_FromString(s.c_str()));
 
    PyObject* res = PyObject_CallObject(detail::_interpreter::get().s_python_function_text, args);
    if (!res)
        throw std::runtime_error("Call to text() failed.");
 
    Py_DECREF(args);
    Py_DECREF(res);
}
 
inline void colorbar(PyObject* mappable = NULL, const std::map<std::string, float>& keywords = {}) {
    if (mappable == NULL)
        throw std::runtime_error("Must call colorbar with PyObject* returned from "
                                 "an image, contour, surface, etc.");
 
    detail::_interpreter::get();
 
    PyObject* args = PyTuple_New(1);
    PyTuple_SetItem(args, 0, mappable);
 
    PyObject* kwargs = PyDict_New();
    for (std::map<std::string, float>::const_iterator it = keywords.begin(); it != keywords.end();
         ++it) {
        PyDict_SetItemString(kwargs, it->first.c_str(), PyFloat_FromDouble(it->second));
    }
 
    PyObject* res =
        PyObject_Call(detail::_interpreter::get().s_python_function_colorbar, args, kwargs);
    if (!res)
        throw std::runtime_error("Call to colorbar() failed.");
 
    Py_DECREF(args);
    Py_DECREF(kwargs);
    Py_DECREF(res);
}
 
inline long figure(long number = -1) {
    detail::_interpreter::get();
 
    PyObject* res;
    if (number == -1)
        res = PyObject_CallObject(detail::_interpreter::get().s_python_function_figure,
                                  detail::_interpreter::get().s_python_empty_tuple);
    else {
        assert(number > 0);
 
        // Make sure interpreter is initialised
        detail::_interpreter::get();
 
        PyObject* args = PyTuple_New(1);
        PyTuple_SetItem(args, 0, PyLong_FromLong(number));
        res = PyObject_CallObject(detail::_interpreter::get().s_python_function_figure, args);
        Py_DECREF(args);
    }
 
    if (!res)
        throw std::runtime_error("Call to figure() failed.");
 
    PyObject* num = PyObject_GetAttrString(res, "number");
    if (!num)
        throw std::runtime_error("Could not get number attribute of figure object");
    const long figureNumber = PyLong_AsLong(num);
 
    Py_DECREF(num);
    Py_DECREF(res);
 
    return figureNumber;
}
 
inline bool fignum_exists(long number) {
    detail::_interpreter::get();
 
    PyObject* args = PyTuple_New(1);
    PyTuple_SetItem(args, 0, PyLong_FromLong(number));
    PyObject* res =
        PyObject_CallObject(detail::_interpreter::get().s_python_function_fignum_exists, args);
    if (!res)
        throw std::runtime_error("Call to fignum_exists() failed.");
 
    bool ret = PyObject_IsTrue(res);
    Py_DECREF(res);
    Py_DECREF(args);
 
    return ret;
}
 
inline void figure_size(size_t w, size_t h) {
    detail::_interpreter::get();
 
    const size_t dpi = 100;
    PyObject* size = PyTuple_New(2);
    PyTuple_SetItem(size, 0, PyFloat_FromDouble((double)w / dpi));
    PyTuple_SetItem(size, 1, PyFloat_FromDouble((double)h / dpi));
 
    PyObject* kwargs = PyDict_New();
    PyDict_SetItemString(kwargs, "figsize", size);
    PyDict_SetItemString(kwargs, "dpi", PyLong_FromSize_t(dpi));
 
    PyObject* res = PyObject_Call(detail::_interpreter::get().s_python_function_figure,
                                  detail::_interpreter::get().s_python_empty_tuple, kwargs);
 
    Py_DECREF(kwargs);
 
    if (!res)
        throw std::runtime_error("Call to figure_size() failed.");
    Py_DECREF(res);
}
 
inline void legend() {
    detail::_interpreter::get();
 
    PyObject* res = PyObject_CallObject(detail::_interpreter::get().s_python_function_legend,
                                        detail::_interpreter::get().s_python_empty_tuple);
    if (!res)
        throw std::runtime_error("Call to legend() failed.");
 
    Py_DECREF(res);
}
 
inline void legend(const std::map<std::string, std::string>& keywords) {
    detail::_interpreter::get();
 
    // construct keyword args
    PyObject* kwargs = PyDict_New();
    for (std::map<std::string, std::string>::const_iterator it = keywords.begin();
         it != keywords.end(); ++it) {
        PyDict_SetItemString(kwargs, it->first.c_str(), PyString_FromString(it->second.c_str()));
    }
 
    PyObject* res = PyObject_Call(detail::_interpreter::get().s_python_function_legend,
                                  detail::_interpreter::get().s_python_empty_tuple, kwargs);
    if (!res)
        throw std::runtime_error("Call to legend() failed.");
 
    Py_DECREF(kwargs);
    Py_DECREF(res);
}
 
template <typename Numeric> inline void set_aspect(Numeric ratio) {
    detail::_interpreter::get();
 
    PyObject* args = PyTuple_New(1);
    PyTuple_SetItem(args, 0, PyFloat_FromDouble(ratio));
    PyObject* kwargs = PyDict_New();
 
    PyObject* ax = PyObject_CallObject(detail::_interpreter::get().s_python_function_gca,
                                       detail::_interpreter::get().s_python_empty_tuple);
    if (!ax)
        throw std::runtime_error("Call to gca() failed.");
    Py_INCREF(ax);
 
    PyObject* set_aspect = PyObject_GetAttrString(ax, "set_aspect");
    if (!set_aspect)
        throw std::runtime_error("Attribute set_aspect not found.");
    Py_INCREF(set_aspect);
 
    PyObject* res = PyObject_Call(set_aspect, args, kwargs);
    if (!res)
        throw std::runtime_error("Call to set_aspect() failed.");
    Py_DECREF(set_aspect);
 
    Py_DECREF(ax);
    Py_DECREF(args);
    Py_DECREF(kwargs);
}
 
inline void set_aspect_equal() {
    // expect ratio == "equal". Leaving error handling to matplotlib.
    detail::_interpreter::get();
 
    PyObject* args = PyTuple_New(1);
    PyTuple_SetItem(args, 0, PyString_FromString("equal"));
    PyObject* kwargs = PyDict_New();
 
    PyObject* ax = PyObject_CallObject(detail::_interpreter::get().s_python_function_gca,
                                       detail::_interpreter::get().s_python_empty_tuple);
    if (!ax)
        throw std::runtime_error("Call to gca() failed.");
    Py_INCREF(ax);
 
    PyObject* set_aspect = PyObject_GetAttrString(ax, "set_aspect");
    if (!set_aspect)
        throw std::runtime_error("Attribute set_aspect not found.");
    Py_INCREF(set_aspect);
 
    PyObject* res = PyObject_Call(set_aspect, args, kwargs);
    if (!res)
        throw std::runtime_error("Call to set_aspect() failed.");
    Py_DECREF(set_aspect);
 
    Py_DECREF(ax);
    Py_DECREF(args);
    Py_DECREF(kwargs);
}
 
template <typename Numeric> void ylim(Numeric left, Numeric right) {
    detail::_interpreter::get();
 
    PyObject* list = PyList_New(2);
    PyList_SetItem(list, 0, PyFloat_FromDouble(left));
    PyList_SetItem(list, 1, PyFloat_FromDouble(right));
 
    PyObject* args = PyTuple_New(1);
    PyTuple_SetItem(args, 0, list);
 
    PyObject* res = PyObject_CallObject(detail::_interpreter::get().s_python_function_ylim, args);
    if (!res)
        throw std::runtime_error("Call to ylim() failed.");
 
    Py_DECREF(args);
    Py_DECREF(res);
}
 
template <typename Numeric> void xlim(Numeric left, Numeric right) {
    detail::_interpreter::get();
 
    PyObject* list = PyList_New(2);
    PyList_SetItem(list, 0, PyFloat_FromDouble(left));
    PyList_SetItem(list, 1, PyFloat_FromDouble(right));
 
    PyObject* args = PyTuple_New(1);
    PyTuple_SetItem(args, 0, list);
 
    PyObject* res = PyObject_CallObject(detail::_interpreter::get().s_python_function_xlim, args);
    if (!res)
        throw std::runtime_error("Call to xlim() failed.");
 
    Py_DECREF(args);
    Py_DECREF(res);
}
 
inline std::array<double, 2> xlim() {
    PyObject* args = PyTuple_New(0);
    PyObject* res = PyObject_CallObject(detail::_interpreter::get().s_python_function_xlim, args);
 
    if (!res)
        throw std::runtime_error("Call to xlim() failed.");
 
    Py_DECREF(res);
 
    PyObject* left = PyTuple_GetItem(res, 0);
    PyObject* right = PyTuple_GetItem(res, 1);
    return {PyFloat_AsDouble(left), PyFloat_AsDouble(right)};
}
 
inline std::array<double, 2> ylim() {
    PyObject* args = PyTuple_New(0);
    PyObject* res = PyObject_CallObject(detail::_interpreter::get().s_python_function_ylim, args);
 
    if (!res)
        throw std::runtime_error("Call to ylim() failed.");
 
    Py_DECREF(res);
 
    PyObject* left = PyTuple_GetItem(res, 0);
    PyObject* right = PyTuple_GetItem(res, 1);
    return {PyFloat_AsDouble(left), PyFloat_AsDouble(right)};
}
 
template <typename Numeric>
inline void xticks(const std::vector<Numeric>& ticks, const std::vector<std::string>& labels = {},
                   const std::map<std::string, std::string>& keywords = {}) {
    assert(labels.size() == 0 || ticks.size() == labels.size());
 
    detail::_interpreter::get();
 
    // using numpy array
    PyObject* ticksarray = detail::get_array(ticks);
 
    PyObject* args;
    if (labels.size() == 0) {
        // construct positional args
        args = PyTuple_New(1);
        PyTuple_SetItem(args, 0, ticksarray);
    } else {
        // make tuple of tick labels
        PyObject* labelstuple = PyTuple_New(labels.size());
        for (size_t i = 0; i < labels.size(); i++)
            PyTuple_SetItem(labelstuple, i, PyUnicode_FromString(labels[i].c_str()));
 
        // construct positional args
        args = PyTuple_New(2);
        PyTuple_SetItem(args, 0, ticksarray);
        PyTuple_SetItem(args, 1, labelstuple);
    }
 
    // construct keyword args
    PyObject* kwargs = PyDict_New();
    for (std::map<std::string, std::string>::const_iterator it = keywords.begin();
         it != keywords.end(); ++it) {
        PyDict_SetItemString(kwargs, it->first.c_str(), PyString_FromString(it->second.c_str()));
    }
 
    PyObject* res =
        PyObject_Call(detail::_interpreter::get().s_python_function_xticks, args, kwargs);
 
    Py_DECREF(args);
    Py_DECREF(kwargs);
    if (!res)
        throw std::runtime_error("Call to xticks() failed");
 
    Py_DECREF(res);
}
 
template <typename Numeric>
inline void xticks(const std::vector<Numeric>& ticks,
                   const std::map<std::string, std::string>& keywords) {
    xticks(ticks, {}, keywords);
}
 
template <typename Numeric>
inline void yticks(const std::vector<Numeric>& ticks, const std::vector<std::string>& labels = {},
                   const std::map<std::string, std::string>& keywords = {}) {
    assert(labels.size() == 0 || ticks.size() == labels.size());
 
    detail::_interpreter::get();
 
    // using numpy array
    PyObject* ticksarray = detail::get_array(ticks);
 
    PyObject* args;
    if (labels.size() == 0) {
        // construct positional args
        args = PyTuple_New(1);
        PyTuple_SetItem(args, 0, ticksarray);
    } else {
        // make tuple of tick labels
        PyObject* labelstuple = PyTuple_New(labels.size());
        for (size_t i = 0; i < labels.size(); i++)
            PyTuple_SetItem(labelstuple, i, PyUnicode_FromString(labels[i].c_str()));
 
        // construct positional args
        args = PyTuple_New(2);
        PyTuple_SetItem(args, 0, ticksarray);
        PyTuple_SetItem(args, 1, labelstuple);
    }
 
    // construct keyword args
    PyObject* kwargs = PyDict_New();
    for (std::map<std::string, std::string>::const_iterator it = keywords.begin();
         it != keywords.end(); ++it) {
        PyDict_SetItemString(kwargs, it->first.c_str(), PyString_FromString(it->second.c_str()));
    }
 
    PyObject* res =
        PyObject_Call(detail::_interpreter::get().s_python_function_yticks, args, kwargs);
 
    Py_DECREF(args);
    Py_DECREF(kwargs);
    if (!res)
        throw std::runtime_error("Call to yticks() failed");
 
    Py_DECREF(res);
}
 
template <typename Numeric>
inline void yticks(const std::vector<Numeric>& ticks,
                   const std::map<std::string, std::string>& keywords) {
    yticks(ticks, {}, keywords);
}
 
template <typename Numeric> inline void margins(Numeric margin) {
    // construct positional args
    PyObject* args = PyTuple_New(1);
    PyTuple_SetItem(args, 0, PyFloat_FromDouble(margin));
 
    PyObject* res =
        PyObject_CallObject(detail::_interpreter::get().s_python_function_margins, args);
    if (!res)
        throw std::runtime_error("Call to margins() failed.");
 
    Py_DECREF(args);
    Py_DECREF(res);
}
 
template <typename Numeric> inline void margins(Numeric margin_x, Numeric margin_y) {
    // construct positional args
    PyObject* args = PyTuple_New(2);
    PyTuple_SetItem(args, 0, PyFloat_FromDouble(margin_x));
    PyTuple_SetItem(args, 1, PyFloat_FromDouble(margin_y));
 
    PyObject* res =
        PyObject_CallObject(detail::_interpreter::get().s_python_function_margins, args);
    if (!res)
        throw std::runtime_error("Call to margins() failed.");
 
    Py_DECREF(args);
    Py_DECREF(res);
}
 
inline void tick_params(const std::map<std::string, std::string>& keywords,
                        const std::string axis = "both") {
    detail::_interpreter::get();
 
    // construct positional args
    PyObject* args;
    args = PyTuple_New(1);
    PyTuple_SetItem(args, 0, PyString_FromString(axis.c_str()));
 
    // construct keyword args
    PyObject* kwargs = PyDict_New();
    for (std::map<std::string, std::string>::const_iterator it = keywords.begin();
         it != keywords.end(); ++it) {
        PyDict_SetItemString(kwargs, it->first.c_str(), PyString_FromString(it->second.c_str()));
    }
 
    PyObject* res =
        PyObject_Call(detail::_interpreter::get().s_python_function_tick_params, args, kwargs);
 
    Py_DECREF(args);
    Py_DECREF(kwargs);
    if (!res)
        throw std::runtime_error("Call to tick_params() failed");
 
    Py_DECREF(res);
}
 
inline void subplot(long nrows, long ncols, long plot_number) {
    detail::_interpreter::get();
 
    // construct positional args
    PyObject* args = PyTuple_New(3);
    PyTuple_SetItem(args, 0, PyFloat_FromDouble(nrows));
    PyTuple_SetItem(args, 1, PyFloat_FromDouble(ncols));
    PyTuple_SetItem(args, 2, PyFloat_FromDouble(plot_number));
 
    PyObject* res =
        PyObject_CallObject(detail::_interpreter::get().s_python_function_subplot, args);
    if (!res)
        throw std::runtime_error("Call to subplot() failed.");
 
    Py_DECREF(args);
    Py_DECREF(res);
}
 
inline void subplot2grid(long nrows, long ncols, long rowid = 0, long colid = 0, long rowspan = 1,
                         long colspan = 1) {
    detail::_interpreter::get();
 
    PyObject* shape = PyTuple_New(2);
    PyTuple_SetItem(shape, 0, PyLong_FromLong(nrows));
    PyTuple_SetItem(shape, 1, PyLong_FromLong(ncols));
 
    PyObject* loc = PyTuple_New(2);
    PyTuple_SetItem(loc, 0, PyLong_FromLong(rowid));
    PyTuple_SetItem(loc, 1, PyLong_FromLong(colid));
 
    PyObject* args = PyTuple_New(4);
    PyTuple_SetItem(args, 0, shape);
    PyTuple_SetItem(args, 1, loc);
    PyTuple_SetItem(args, 2, PyLong_FromLong(rowspan));
    PyTuple_SetItem(args, 3, PyLong_FromLong(colspan));
 
    PyObject* res =
        PyObject_CallObject(detail::_interpreter::get().s_python_function_subplot2grid, args);
    if (!res)
        throw std::runtime_error("Call to subplot2grid() failed.");
 
    Py_DECREF(shape);
    Py_DECREF(loc);
    Py_DECREF(args);
    Py_DECREF(res);
}
 
inline void title(const std::string& titlestr,
                  const std::map<std::string, std::string>& keywords = {}) {
    detail::_interpreter::get();
 
    PyObject* pytitlestr = PyString_FromString(titlestr.c_str());
    PyObject* args = PyTuple_New(1);
    PyTuple_SetItem(args, 0, pytitlestr);
 
    PyObject* kwargs = PyDict_New();
    for (auto it = keywords.begin(); it != keywords.end(); ++it) {
        PyDict_SetItemString(kwargs, it->first.c_str(), PyUnicode_FromString(it->second.c_str()));
    }
 
    PyObject* res =
        PyObject_Call(detail::_interpreter::get().s_python_function_title, args, kwargs);
    if (!res)
        throw std::runtime_error("Call to title() failed.");
 
    Py_DECREF(args);
    Py_DECREF(kwargs);
    Py_DECREF(res);
}
 
inline void suptitle(const std::string& suptitlestr,
                     const std::map<std::string, std::string>& keywords = {}) {
    detail::_interpreter::get();
 
    PyObject* pysuptitlestr = PyString_FromString(suptitlestr.c_str());
    PyObject* args = PyTuple_New(1);
    PyTuple_SetItem(args, 0, pysuptitlestr);
 
    PyObject* kwargs = PyDict_New();
    for (auto it = keywords.begin(); it != keywords.end(); ++it) {
        PyDict_SetItemString(kwargs, it->first.c_str(), PyUnicode_FromString(it->second.c_str()));
    }
 
    PyObject* res =
        PyObject_Call(detail::_interpreter::get().s_python_function_suptitle, args, kwargs);
    if (!res)
        throw std::runtime_error("Call to suptitle() failed.");
 
    Py_DECREF(args);
    Py_DECREF(kwargs);
    Py_DECREF(res);
}
 
inline void axis(const std::string& axisstr) {
    detail::_interpreter::get();
 
    PyObject* str = PyString_FromString(axisstr.c_str());
    PyObject* args = PyTuple_New(1);
    PyTuple_SetItem(args, 0, str);
 
    PyObject* res = PyObject_CallObject(detail::_interpreter::get().s_python_function_axis, args);
    if (!res)
        throw std::runtime_error("Call to title() failed.");
 
    Py_DECREF(args);
    Py_DECREF(res);
}
 
inline void
axhline(double y, double xmin = 0., double xmax = 1.,
        const std::map<std::string, std::string>& keywords = std::map<std::string, std::string>()) {
    detail::_interpreter::get();
 
    // construct positional args
    PyObject* args = PyTuple_New(3);
    PyTuple_SetItem(args, 0, PyFloat_FromDouble(y));
    PyTuple_SetItem(args, 1, PyFloat_FromDouble(xmin));
    PyTuple_SetItem(args, 2, PyFloat_FromDouble(xmax));
 
    // construct keyword args
    PyObject* kwargs = PyDict_New();
    for (std::map<std::string, std::string>::const_iterator it = keywords.begin();
         it != keywords.end(); ++it) {
        PyDict_SetItemString(kwargs, it->first.c_str(), PyString_FromString(it->second.c_str()));
    }
 
    PyObject* res =
        PyObject_Call(detail::_interpreter::get().s_python_function_axhline, args, kwargs);
 
    Py_DECREF(args);
    Py_DECREF(kwargs);
 
    if (res)
        Py_DECREF(res);
}
 
inline void
axvline(double x, double ymin = 0., double ymax = 1.,
        const std::map<std::string, std::string>& keywords = std::map<std::string, std::string>()) {
    detail::_interpreter::get();
 
    // construct positional args
    PyObject* args = PyTuple_New(3);
    PyTuple_SetItem(args, 0, PyFloat_FromDouble(x));
    PyTuple_SetItem(args, 1, PyFloat_FromDouble(ymin));
    PyTuple_SetItem(args, 2, PyFloat_FromDouble(ymax));
 
    // construct keyword args
    PyObject* kwargs = PyDict_New();
    for (std::map<std::string, std::string>::const_iterator it = keywords.begin();
         it != keywords.end(); ++it) {
        PyDict_SetItemString(kwargs, it->first.c_str(), PyString_FromString(it->second.c_str()));
    }
 
    PyObject* res =
        PyObject_Call(detail::_interpreter::get().s_python_function_axvline, args, kwargs);
 
    Py_DECREF(args);
    Py_DECREF(kwargs);
 
    if (res)
        Py_DECREF(res);
}
 
inline void
axvspan(double xmin, double xmax, double ymin = 0., double ymax = 1.,
        const std::map<std::string, std::string>& keywords = std::map<std::string, std::string>()) {
    // construct positional args
    PyObject* args = PyTuple_New(4);
    PyTuple_SetItem(args, 0, PyFloat_FromDouble(xmin));
    PyTuple_SetItem(args, 1, PyFloat_FromDouble(xmax));
    PyTuple_SetItem(args, 2, PyFloat_FromDouble(ymin));
    PyTuple_SetItem(args, 3, PyFloat_FromDouble(ymax));
 
    // construct keyword args
    PyObject* kwargs = PyDict_New();
    for (auto it = keywords.begin(); it != keywords.end(); ++it) {
        if (it->first == "linewidth" || it->first == "alpha") {
            PyDict_SetItemString(kwargs, it->first.c_str(),
                                 PyFloat_FromDouble(std::stod(it->second)));
        } else {
            PyDict_SetItemString(kwargs, it->first.c_str(),
                                 PyString_FromString(it->second.c_str()));
        }
    }
 
    PyObject* res =
        PyObject_Call(detail::_interpreter::get().s_python_function_axvspan, args, kwargs);
    Py_DECREF(args);
    Py_DECREF(kwargs);
 
    if (res)
        Py_DECREF(res);
}
 
inline void xlabel(const std::string& str,
                   const std::map<std::string, std::string>& keywords = {}) {
    detail::_interpreter::get();
 
    PyObject* pystr = PyString_FromString(str.c_str());
    PyObject* args = PyTuple_New(1);
    PyTuple_SetItem(args, 0, pystr);
 
    PyObject* kwargs = PyDict_New();
    for (auto it = keywords.begin(); it != keywords.end(); ++it) {
        PyDict_SetItemString(kwargs, it->first.c_str(), PyUnicode_FromString(it->second.c_str()));
    }
 
    PyObject* res =
        PyObject_Call(detail::_interpreter::get().s_python_function_xlabel, args, kwargs);
    if (!res)
        throw std::runtime_error("Call to xlabel() failed.");
 
    Py_DECREF(args);
    Py_DECREF(kwargs);
    Py_DECREF(res);
}
 
inline void ylabel(const std::string& str,
                   const std::map<std::string, std::string>& keywords = {}) {
    detail::_interpreter::get();
 
    PyObject* pystr = PyString_FromString(str.c_str());
    PyObject* args = PyTuple_New(1);
    PyTuple_SetItem(args, 0, pystr);
 
    PyObject* kwargs = PyDict_New();
    for (auto it = keywords.begin(); it != keywords.end(); ++it) {
        PyDict_SetItemString(kwargs, it->first.c_str(), PyUnicode_FromString(it->second.c_str()));
    }
 
    PyObject* res =
        PyObject_Call(detail::_interpreter::get().s_python_function_ylabel, args, kwargs);
    if (!res)
        throw std::runtime_error("Call to ylabel() failed.");
 
    Py_DECREF(args);
    Py_DECREF(kwargs);
    Py_DECREF(res);
}
 
inline void set_zlabel(const std::string& str,
                       const std::map<std::string, std::string>& keywords = {}) {
    detail::_interpreter::get();
 
    // Same as with plot_surface: We lazily load the modules here the first time
    // this function is called because I'm not sure that we can assume "matplotlib
    // installed" implies "mpl_toolkits installed" on all platforms, and we don't
    // want to require it for people who don't need 3d plots.
    static PyObject *mpl_toolkitsmod = nullptr, *axis3dmod = nullptr;
    if (!mpl_toolkitsmod) {
        PyObject* mpl_toolkits = PyString_FromString("mpl_toolkits");
        PyObject* axis3d = PyString_FromString("mpl_toolkits.mplot3d");
        if (!mpl_toolkits || !axis3d) {
            throw std::runtime_error("couldnt create string");
        }
 
        mpl_toolkitsmod = PyImport_Import(mpl_toolkits);
        Py_DECREF(mpl_toolkits);
        if (!mpl_toolkitsmod) {
            throw std::runtime_error("Error loading module mpl_toolkits!");
        }
 
        axis3dmod = PyImport_Import(axis3d);
        Py_DECREF(axis3d);
        if (!axis3dmod) {
            throw std::runtime_error("Error loading module mpl_toolkits.mplot3d!");
        }
    }
 
    PyObject* pystr = PyString_FromString(str.c_str());
    PyObject* args = PyTuple_New(1);
    PyTuple_SetItem(args, 0, pystr);
 
    PyObject* kwargs = PyDict_New();
    for (auto it = keywords.begin(); it != keywords.end(); ++it) {
        PyDict_SetItemString(kwargs, it->first.c_str(), PyUnicode_FromString(it->second.c_str()));
    }
 
    PyObject* ax = PyObject_CallObject(detail::_interpreter::get().s_python_function_gca,
                                       detail::_interpreter::get().s_python_empty_tuple);
    if (!ax)
        throw std::runtime_error("Call to gca() failed.");
    Py_INCREF(ax);
 
    PyObject* zlabel = PyObject_GetAttrString(ax, "set_zlabel");
    if (!zlabel)
        throw std::runtime_error("Attribute set_zlabel not found.");
    Py_INCREF(zlabel);
 
    PyObject* res = PyObject_Call(zlabel, args, kwargs);
    if (!res)
        throw std::runtime_error("Call to set_zlabel() failed.");
    Py_DECREF(zlabel);
 
    Py_DECREF(ax);
    Py_DECREF(args);
    Py_DECREF(kwargs);
    if (res)
        Py_DECREF(res);
}
 
inline void grid(bool flag) {
    detail::_interpreter::get();
 
    PyObject* pyflag = flag ? Py_True : Py_False;
    Py_INCREF(pyflag);
 
    PyObject* args = PyTuple_New(1);
    PyTuple_SetItem(args, 0, pyflag);
 
    PyObject* res = PyObject_CallObject(detail::_interpreter::get().s_python_function_grid, args);
    if (!res)
        throw std::runtime_error("Call to grid() failed.");
 
    Py_DECREF(args);
    Py_DECREF(res);
}
 
inline void show(const bool block = true) {
    detail::_interpreter::get();
 
    PyObject* res;
    if (block) {
        res = PyObject_CallObject(detail::_interpreter::get().s_python_function_show,
                                  detail::_interpreter::get().s_python_empty_tuple);
    } else {
        PyObject* kwargs = PyDict_New();
        PyDict_SetItemString(kwargs, "block", Py_False);
        res = PyObject_Call(detail::_interpreter::get().s_python_function_show,
                            detail::_interpreter::get().s_python_empty_tuple, kwargs);
        Py_DECREF(kwargs);
    }
 
    if (!res)
        throw std::runtime_error("Call to show() failed.");
 
    Py_DECREF(res);
}
 
inline void close() {
    detail::_interpreter::get();
 
    PyObject* res = PyObject_CallObject(detail::_interpreter::get().s_python_function_close,
                                        detail::_interpreter::get().s_python_empty_tuple);
 
    if (!res)
        throw std::runtime_error("Call to close() failed.");
 
    Py_DECREF(res);
}
 
inline void xkcd() {
    detail::_interpreter::get();
 
    PyObject* res;
    PyObject* kwargs = PyDict_New();
 
    res = PyObject_Call(detail::_interpreter::get().s_python_function_xkcd,
                        detail::_interpreter::get().s_python_empty_tuple, kwargs);
 
    Py_DECREF(kwargs);
 
    if (!res)
        throw std::runtime_error("Call to show() failed.");
 
    Py_DECREF(res);
}
 
inline void draw() {
    detail::_interpreter::get();
 
    PyObject* res = PyObject_CallObject(detail::_interpreter::get().s_python_function_draw,
                                        detail::_interpreter::get().s_python_empty_tuple);
 
    if (!res)
        throw std::runtime_error("Call to draw() failed.");
 
    Py_DECREF(res);
}
 
template <typename Numeric> inline void pause(Numeric interval) {
    detail::_interpreter::get();
 
    PyObject* args = PyTuple_New(1);
    PyTuple_SetItem(args, 0, PyFloat_FromDouble(interval));
 
    PyObject* res = PyObject_CallObject(detail::_interpreter::get().s_python_function_pause, args);
    if (!res)
        throw std::runtime_error("Call to pause() failed.");
 
    Py_DECREF(args);
    Py_DECREF(res);
}
 
inline void save(const std::string& filename, const int dpi = 0) {
    detail::_interpreter::get();
 
    PyObject* pyfilename = PyString_FromString(filename.c_str());
 
    PyObject* args = PyTuple_New(1);
    PyTuple_SetItem(args, 0, pyfilename);
 
    PyObject* kwargs = PyDict_New();
 
    if (dpi > 0) {
        PyDict_SetItemString(kwargs, "dpi", PyLong_FromLong(dpi));
    }
 
    PyObject* res = PyObject_Call(detail::_interpreter::get().s_python_function_save, args, kwargs);
    if (!res)
        throw std::runtime_error("Call to save() failed.");
 
    Py_DECREF(args);
    Py_DECREF(kwargs);
    Py_DECREF(res);
}
 
inline void rcparams(const std::map<std::string, std::string>& keywords = {}) {
    detail::_interpreter::get();
    PyObject* args = PyTuple_New(0);
    PyObject* kwargs = PyDict_New();
    for (auto it = keywords.begin(); it != keywords.end(); ++it) {
        if ("text.usetex" == it->first)
            PyDict_SetItemString(kwargs, it->first.c_str(),
                                 PyLong_FromLong(std::stoi(it->second.c_str())));
        else
            PyDict_SetItemString(kwargs, it->first.c_str(),
                                 PyString_FromString(it->second.c_str()));
    }
 
    PyObject* update =
        PyObject_GetAttrString(detail::_interpreter::get().s_python_function_rcparams, "update");
    PyObject* res = PyObject_Call(update, args, kwargs);
    if (!res)
        throw std::runtime_error("Call to rcParams.update() failed.");
    Py_DECREF(args);
    Py_DECREF(kwargs);
    Py_DECREF(update);
    Py_DECREF(res);
}
 
inline void clf() {
    detail::_interpreter::get();
 
    PyObject* res = PyObject_CallObject(detail::_interpreter::get().s_python_function_clf,
                                        detail::_interpreter::get().s_python_empty_tuple);
 
    if (!res)
        throw std::runtime_error("Call to clf() failed.");
 
    Py_DECREF(res);
}
 
inline void cla() {
    detail::_interpreter::get();
 
    PyObject* res = PyObject_CallObject(detail::_interpreter::get().s_python_function_cla,
                                        detail::_interpreter::get().s_python_empty_tuple);
 
    if (!res)
        throw std::runtime_error("Call to cla() failed.");
 
    Py_DECREF(res);
}
 
inline void ion() {
    detail::_interpreter::get();
 
    PyObject* res = PyObject_CallObject(detail::_interpreter::get().s_python_function_ion,
                                        detail::_interpreter::get().s_python_empty_tuple);
 
    if (!res)
        throw std::runtime_error("Call to ion() failed.");
 
    Py_DECREF(res);
}
 
inline std::vector<std::array<double, 2>>
ginput(const int numClicks = 1, const std::map<std::string, std::string>& keywords = {}) {
    detail::_interpreter::get();
 
    PyObject* args = PyTuple_New(1);
    PyTuple_SetItem(args, 0, PyLong_FromLong(numClicks));
 
    // construct keyword args
    PyObject* kwargs = PyDict_New();
    for (std::map<std::string, std::string>::const_iterator it = keywords.begin();
         it != keywords.end(); ++it) {
        PyDict_SetItemString(kwargs, it->first.c_str(), PyUnicode_FromString(it->second.c_str()));
    }
 
    PyObject* res =
        PyObject_Call(detail::_interpreter::get().s_python_function_ginput, args, kwargs);
 
    Py_DECREF(kwargs);
    Py_DECREF(args);
    if (!res)
        throw std::runtime_error("Call to ginput() failed.");
 
    const size_t len = PyList_Size(res);
    std::vector<std::array<double, 2>> out;
    out.reserve(len);
    for (size_t i = 0; i < len; i++) {
        PyObject* current = PyList_GetItem(res, i);
        std::array<double, 2> position;
        position[0] = PyFloat_AsDouble(PyTuple_GetItem(current, 0));
        position[1] = PyFloat_AsDouble(PyTuple_GetItem(current, 1));
        out.push_back(position);
    }
    Py_DECREF(res);
 
    return out;
}
 
// Actually, is there any reason not to call this automatically for every plot?
inline void tight_layout() {
    detail::_interpreter::get();
 
    PyObject* res = PyObject_CallObject(detail::_interpreter::get().s_python_function_tight_layout,
                                        detail::_interpreter::get().s_python_empty_tuple);
 
    if (!res)
        throw std::runtime_error("Call to tight_layout() failed.");
 
    Py_DECREF(res);
}
 
// Support for variadic plot() and initializer lists:
 
namespace detail {
 
template <typename T>
using is_function = typename std::is_function<std::remove_pointer<std::remove_reference<T>>>::type;
 
template <bool obj, typename T> struct is_callable_impl;
 
template <typename T> struct is_callable_impl<false, T> {
    typedef is_function<T> type;
}; // a non-object is callable iff it is a function
 
template <typename T> struct is_callable_impl<true, T> {
    struct Fallback {
        void operator()();
    };
    struct Derived : T, Fallback {};
 
    template <typename U, U> struct Check;
 
    template <typename U>
    static std::true_type test(...); // use a variadic function to make sure (1) it accepts
                                     // everything and (2) its always the worst match
 
    template <typename U> static std::false_type test(Check<void (Fallback::*)(), &U::operator()>*);
 
  public:
    typedef decltype(test<Derived>(nullptr)) type;
    typedef decltype(&Fallback::operator()) dtype;
    static constexpr bool value = type::value;
}; // an object is callable iff it defines operator()
 
template <typename T> struct is_callable {
    // dispatch to is_callable_impl<true, T> or is_callable_impl<false, T>
    // depending on whether T is of class type or not
    typedef typename is_callable_impl<std::is_class<T>::value, T>::type type;
};
 
template <typename IsYDataCallable> struct plot_impl {};
 
template <> struct plot_impl<std::false_type> {
    template <typename IterableX, typename IterableY>
    bool operator()(const IterableX& x, const IterableY& y, const std::string& format) {
        detail::_interpreter::get();
 
        // 2-phase lookup for distance, begin, end
        using std::begin;
        using std::distance;
        using std::end;
 
        auto xs = distance(begin(x), end(x));
        auto ys = distance(begin(y), end(y));
        assert(xs == ys && "x and y data must have the same number of elements!");
 
        PyObject* xlist = PyList_New(xs);
        PyObject* ylist = PyList_New(ys);
        PyObject* pystring = PyString_FromString(format.c_str());
 
        auto itx = begin(x), ity = begin(y);
        for (size_t i = 0; i < xs; ++i) {
            PyList_SetItem(xlist, i, PyFloat_FromDouble(*itx++));
            PyList_SetItem(ylist, i, PyFloat_FromDouble(*ity++));
        }
 
        PyObject* plot_args = PyTuple_New(3);
        PyTuple_SetItem(plot_args, 0, xlist);
        PyTuple_SetItem(plot_args, 1, ylist);
        PyTuple_SetItem(plot_args, 2, pystring);
 
        PyObject* res =
            PyObject_CallObject(detail::_interpreter::get().s_python_function_plot, plot_args);
 
        Py_DECREF(plot_args);
        if (res)
            Py_DECREF(res);
 
        return res;
    }
};
 
template <> struct plot_impl<std::true_type> {
    template <typename Iterable, typename Callable>
    bool operator()(const Iterable& ticks, const Callable& f, const std::string& format) {
        if (begin(ticks) == end(ticks))
            return true;
 
        // We could use additional meta-programming to deduce the correct element
        // type of y, but all values have to be convertible to double anyways
        std::vector<double> y;
        for (auto x : ticks)
            y.push_back(f(x));
        return plot_impl<std::false_type>()(ticks, y, format);
    }
};
 
} // end namespace detail
 
// recursion stop for the above
template <typename... Args> bool plot() {
    return true;
}
 
template <typename A, typename B, typename... Args>
bool plot(const A& a, const B& b, const std::string& format, Args... args) {
    return detail::plot_impl<typename detail::is_callable<B>::type>()(a, b, format) &&
           plot(args...);
}
 
/*
 * This group of plot() functions is needed to support initializer lists, i.e.
 * calling plot( {1,2,3,4} )
 */
inline bool plot(const std::vector<double>& x, const std::vector<double>& y,
                 const std::string& format = "") {
    return plot<double, double>(x, y, format);
}
 
inline bool plot(const std::vector<double>& y, const std::string& format = "") {
    return plot<double>(y, format);
}
 
inline bool plot(const std::vector<double>& x, const std::vector<double>& y,
                 const std::map<std::string, std::string>& keywords) {
    return plot<double>(x, y, keywords);
}
 
/*
 * This class allows dynamic plots, ie changing the plotted data without
 * clearing and re-plotting
 */
class Plot {
  public:
    // default initialization with plot label, some data and format
    template <typename Numeric>
    Plot(const std::string& name, const std::vector<Numeric>& x, const std::vector<Numeric>& y,
         const std::string& format = "") {
        detail::_interpreter::get();
 
        assert(x.size() == y.size());
 
        PyObject* kwargs = PyDict_New();
        if (name != "")
            PyDict_SetItemString(kwargs, "label", PyString_FromString(name.c_str()));
 
        PyObject* xarray = detail::get_array(x);
        PyObject* yarray = detail::get_array(y);
 
        PyObject* pystring = PyString_FromString(format.c_str());
 
        PyObject* plot_args = PyTuple_New(3);
        PyTuple_SetItem(plot_args, 0, xarray);
        PyTuple_SetItem(plot_args, 1, yarray);
        PyTuple_SetItem(plot_args, 2, pystring);
 
        PyObject* res =
            PyObject_Call(detail::_interpreter::get().s_python_function_plot, plot_args, kwargs);
 
        Py_DECREF(kwargs);
        Py_DECREF(plot_args);
 
        if (res) {
            line = PyList_GetItem(res, 0);
 
            if (line)
                set_data_fct = PyObject_GetAttrString(line, "set_data");
            else
                Py_DECREF(line);
            Py_DECREF(res);
        }
    }
 
    // shorter initialization with name or format only
    // basically calls line, = plot([], [])
    Plot(const std::string& name = "", const std::string& format = "")
        : Plot(name, std::vector<double>(), std::vector<double>(), format) {}
 
    template <typename Numeric>
    bool update(const std::vector<Numeric>& x, const std::vector<Numeric>& y) {
        assert(x.size() == y.size());
        if (set_data_fct) {
            PyObject* xarray = detail::get_array(x);
            PyObject* yarray = detail::get_array(y);
 
            PyObject* plot_args = PyTuple_New(2);
            PyTuple_SetItem(plot_args, 0, xarray);
            PyTuple_SetItem(plot_args, 1, yarray);
 
            PyObject* res = PyObject_CallObject(set_data_fct, plot_args);
            if (res)
                Py_DECREF(res);
            return res;
        }
        return false;
    }
 
    // clears the plot but keep it available
    bool clear() { return update(std::vector<double>(), std::vector<double>()); }
 
    // definitely remove this line
    void remove() {
        if (line) {
            auto remove_fct = PyObject_GetAttrString(line, "remove");
            PyObject* args = PyTuple_New(0);
            PyObject* res = PyObject_CallObject(remove_fct, args);
            if (res)
                Py_DECREF(res);
        }
        decref();
    }
 
    ~Plot() { decref(); }
 
  private:
    void decref() {
        if (line)
            Py_DECREF(line);
        if (set_data_fct)
            Py_DECREF(set_data_fct);
    }
 
    PyObject* line = nullptr;
    PyObject* set_data_fct = nullptr;
};
 
} // end namespace matplotlibcpp