matplotlibcpp.h

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#pragma once
 
#include <algorithm>
#include <array>
#include <cstdint> // <cstdint> requires c++11 support
#include <functional>
#include <iostream>
#include <map>
#include <numeric>
#include <stdexcept>
#include <vector>
 
#include <Python.h>
 
#define WITHOUT_NUMPY
 
#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
#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_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_boxplot;
  PyObject *s_python_function_stackplot;
  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_subplot;
  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_xlabel;
  PyObject *s_python_function_ylabel;
  PyObject *s_python_function_xticks;
  PyObject *s_python_function_yticks;
  PyObject *s_python_function_grid;
  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_subplots_adjust;
 
  /* 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.
      http://bytes.com/topic/python/answers/793370-multiple-independent-python-interpreters-c-c-program
     */
 
  static _interpreter &get() {
    static _interpreter ctx;
    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();
 
#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_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_boxplot = safe_import(pymod, "boxplot");
    s_python_function_stackplot = safe_import(pymod, "stackplot");
    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_subplot = safe_import(pymod, "subplot");
    s_python_function_legend = safe_import(pymod, "legend");
    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_xlabel = safe_import(pymod, "xlabel");
    s_python_function_ylabel = safe_import(pymod, "ylabel");
    s_python_function_xticks = safe_import(pymod, "xticks");
    s_python_function_yticks = safe_import(pymod, "yticks");
    s_python_function_grid = safe_import(pymod, "grid");
    s_python_function_xlim = safe_import(pymod, "xlim");
    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_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_subplots_adjust = safe_import(pymod, "subplots_adjust");
#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
 
// must be called before the first regular call to matplotlib to have any effect
inline void backend(const std::string &name) { detail::s_backend = name; }
 
inline bool annotate(std::string annotation, double x, double y) {
  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;
}
 
#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; };
 
template <typename Numeric> PyObject *get_array(const std::vector<Numeric> &v) {
  detail::_interpreter::get(); // interpreter needs to be initialized for the numpy commands to work
  NPY_TYPES type = select_npy_type<Numeric>::type;
  if (type == NPY_NOTYPE) {
    std::vector<double> vd(v.size());
    npy_intp vsize = v.size();
    std::copy(v.begin(), v.end(), vd.begin());
    PyObject *varray = PyArray_SimpleNewFromData(1, &vsize, NPY_DOUBLE, (void *)(vd.data()));
    return varray;
  }
 
  npy_intp vsize = v.size();
  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) {
  detail::_interpreter::get(); // interpreter needs to be initialized for the numpy commands to work
  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
 
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());
 
  // using numpy arrays
  PyObject *xarray = get_array(x);
  PyObject *yarray = 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;
}
 
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>()) {
  // 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 = get_2darray(x);
  PyObject *yarray = get_2darray(y);
  PyObject *zarray = 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) {
    PyDict_SetItemString(kwargs, it->first.c_str(), PyString_FromString(it->second.c_str()));
  }
 
  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);
 
  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>
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());
 
  // using numpy arrays
  PyObject *xarray = get_array(x);
  PyObject *yarray = 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());
 
  // using numpy arrays
  PyObject *xarray = get_array(x);
  PyObject *yarray = 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());
 
  // using numpy arrays
  PyObject *xarray = get_array(x);
  PyObject *y1array = get_array(y1);
  PyObject *y2array = 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 hist(const std::vector<Numeric> &y, long bins = 10, std::string color = "b", double alpha = 1.0, bool cumulative = false) {
 
  PyObject *yarray = 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 internal {
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) {
  assert(type == NPY_UINT8 || type == NPY_FLOAT);
  assert(colors == 1 || colors == 3 || colors == 4);
 
  detail::_interpreter::get(); // interpreter needs to be initialized for the numpy commands to work
 
  // 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");
  Py_DECREF(res);
}
} // namespace internal
 
void imshow(const unsigned char *ptr, const int rows, const int columns, const int colors,
            const std::map<std::string, std::string> &keywords = {}) {
  internal::imshow((void *)ptr, NPY_UINT8, rows, columns, colors, keywords);
}
 
void imshow(const float *ptr, const int rows, const int columns, const int colors,
            const std::map<std::string, std::string> &keywords = {}) {
  internal::imshow((void *)ptr, NPY_FLOAT, rows, columns, colors, keywords);
}
 
#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);
  }
 
  internal::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
{
  assert(x.size() == y.size());
 
  PyObject *xarray = get_array(x);
  PyObject *yarray = get_array(y);
 
  PyObject *kwargs = PyDict_New();
  PyDict_SetItemString(kwargs, "s", PyLong_FromLong(s));
 
  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 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 = {}) {
  PyObject *yarray = get_array(y);
 
  std::vector<int> x;
  for (int i = 0; i < y.size(); i++)
    x.push_back(i);
 
  PyObject *xarray = get_array(x);
 
  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));
 
  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;
}
 
inline bool subplots_adjust(const std::map<std::string, double> &keywords = {}) {
 
  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) {
  PyObject *yarray = 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());
 
  PyObject *xarray = get_array(x);
  PyObject *yarray = 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 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());
 
  PyObject *xarray = get_array(x);
  PyObject *yarray = get_array(y);
  PyObject *uarray = get_array(u);
  PyObject *warray = 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>
bool boxplot(const std::vector<NumericX> &x, const double &position, const double &width, const std::string &color,
             const std::string &linestyle, const std::map<std::string, std::string> &keywords = {}, bool vert = true) {
 
  // Create a sequence of vectors
  PyObject *plot_args = PyTuple_New(1);
  PyTuple_SetItem(plot_args, 0, get_array(x));
 
  // 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()));
  }
 
  // append position
  PyObject *positions = PyTuple_New(1);
  PyTuple_SetItem(positions, 0, PyFloat_FromDouble(position));
  PyDict_SetItemString(kwargs, "positions", positions);
 
  // append width (can be scalar or tuple)
  PyDict_SetItemString(kwargs, "widths", PyFloat_FromDouble(width));
 
  // append color setting to all lines
  PyObject *cargs1 = PyDict_New();
  PyDict_SetItemString(cargs1, "color", PyUnicode_FromString(color.c_str()));
  PyDict_SetItemString(cargs1, "linestyle", PyUnicode_FromString(linestyle.c_str()));
  PyDict_SetItemString(kwargs, "capprops", cargs1);
  PyDict_SetItemString(kwargs, "whiskerprops", cargs1);
  PyDict_SetItemString(kwargs, "medianprops", cargs1);
  PyDict_SetItemString(kwargs, "boxprops", cargs1);
 
  // set if vertical or not
  if (vert)
    PyDict_SetItemString(kwargs, "vert", Py_True);
  else
    PyDict_SetItemString(kwargs, "vert", Py_False);
 
  // finally call the external python function
  PyObject *res = PyObject_Call(detail::_interpreter::get().s_python_function_boxplot, plot_args, kwargs);
 
  Py_DECREF(kwargs);
  Py_DECREF(plot_args);
  if (res)
    Py_DECREF(res);
  return res;
}
 
template <typename NumericX, typename NumericY>
bool stackplot(const std::vector<NumericX> &x, const std::vector<std::vector<NumericY>> &ys, const std::vector<std::string> &labels,
               const std::vector<std::string> &colors, const std::string &baseline = "zero") {
 
  // assert we have enough labels and colors to go around
  assert(ys.size() == labels.size());
  assert(ys.size() == colors.size());
 
  // Append the datapoints
  PyObject *plot_args = PyTuple_New(1 + (int)ys.size());
  PyTuple_SetItem(plot_args, 0, get_array(x));
  for (size_t i = 0; i < ys.size(); i++) {
    assert(x.size() == ys.at(i).size());
    PyTuple_SetItem(plot_args, 1 + (int)i, get_array(ys.at(i)));
  }
 
  // Labels
  PyObject *list_labels = PyList_New(labels.size());
  for (size_t i = 0; i < labels.size(); i++) {
    PyList_SetItem(list_labels, i, PyString_FromString(labels.at(i).c_str()));
  }
 
  // Colors
  PyObject *list_colors = PyList_New(colors.size());
  for (size_t i = 0; i < colors.size(); i++) {
    PyList_SetItem(list_colors, i, PyString_FromString(colors.at(i).c_str()));
  }
 
  // append the baseline [‘zero’, ‘sym’, ‘wiggle’, ‘weighted_wiggle’]
  PyObject *kwargs = PyDict_New();
  PyDict_SetItemString(kwargs, "baseline", PyUnicode_FromString(baseline.c_str()));
  PyDict_SetItemString(kwargs, "labels", list_labels);
  PyDict_SetItemString(kwargs, "colors", list_colors);
  PyDict_SetItemString(kwargs, "edgecolors", PyUnicode_FromString("none"));
 
  // finally call the external python function
  PyObject *res = PyObject_Call(detail::_interpreter::get().s_python_function_stackplot, plot_args, kwargs);
 
  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());
 
  PyObject *xarray = get_array(x);
  PyObject *yarray = 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());
 
  PyObject *xarray = get_array(x);
  PyObject *yarray = 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());
 
  PyObject *xarray = get_array(x);
  PyObject *yarray = 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());
 
  PyObject *xarray = get_array(x);
  PyObject *yarray = 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());
 
  PyObject *xarray = get_array(x);
  PyObject *yarray = get_array(y);
  PyObject *yerrarray = 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 = "") {
  PyObject *kwargs = PyDict_New();
  PyDict_SetItemString(kwargs, "label", PyString_FromString(name.c_str()));
 
  PyObject *yarray = 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 Numeric>
bool named_plot(const std::string &name, const std::vector<Numeric> &x, const std::vector<Numeric> &y, const std::string &format = "") {
  PyObject *kwargs = PyDict_New();
  PyDict_SetItemString(kwargs, "label", PyString_FromString(name.c_str()));
 
  PyObject *xarray = get_array(x);
  PyObject *yarray = 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 Numeric>
bool named_semilogx(const std::string &name, const std::vector<Numeric> &x, const std::vector<Numeric> &y, const std::string &format = "") {
  PyObject *kwargs = PyDict_New();
  PyDict_SetItemString(kwargs, "label", PyString_FromString(name.c_str()));
 
  PyObject *xarray = get_array(x);
  PyObject *yarray = 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 Numeric>
bool named_semilogy(const std::string &name, const std::vector<Numeric> &x, const std::vector<Numeric> &y, const std::string &format = "") {
  PyObject *kwargs = PyDict_New();
  PyDict_SetItemString(kwargs, "label", PyString_FromString(name.c_str()));
 
  PyObject *xarray = get_array(x);
  PyObject *yarray = 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 Numeric>
bool named_loglog(const std::string &name, const std::vector<Numeric> &x, const std::vector<Numeric> &y, const std::string &format = "") {
  PyObject *kwargs = PyDict_New();
  PyDict_SetItemString(kwargs, "label", PyString_FromString(name.c_str()));
 
  PyObject *xarray = get_array(x);
  PyObject *yarray = 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 = "") {
  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 long figure(long number = -1) {
  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) {
  // Make sure interpreter is initialised
  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) {
  // Make sure interpreter is initialised
  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() {
  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);
}
 
template <typename Numeric> void ylim(Numeric left, Numeric right) {
  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) {
  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 double *xlim() {
  PyObject *args = PyTuple_New(0);
  PyObject *res = PyObject_CallObject(detail::_interpreter::get().s_python_function_xlim, args);
  PyObject *left = PyTuple_GetItem(res, 0);
  PyObject *right = PyTuple_GetItem(res, 1);
 
  double *arr = new double[2];
  arr[0] = PyFloat_AsDouble(left);
  arr[1] = PyFloat_AsDouble(right);
 
  if (!res)
    throw std::runtime_error("Call to xlim() failed.");
 
  Py_DECREF(res);
  return arr;
}
 
inline double *ylim() {
  PyObject *args = PyTuple_New(0);
  PyObject *res = PyObject_CallObject(detail::_interpreter::get().s_python_function_ylim, args);
  PyObject *left = PyTuple_GetItem(res, 0);
  PyObject *right = PyTuple_GetItem(res, 1);
 
  double *arr = new double[2];
  arr[0] = PyFloat_AsDouble(left);
  arr[1] = PyFloat_AsDouble(right);
 
  if (!res)
    throw std::runtime_error("Call to ylim() failed.");
 
  Py_DECREF(res);
  return arr;
}
 
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());
 
  // using numpy array
  PyObject *ticksarray = 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());
 
  // using numpy array
  PyObject *ticksarray = 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);
}
 
inline void subplot(long nrows, long ncols, long plot_number) {
  // construct positional args
  PyObject *args = PyTuple_New(3);
  PyTuple_SetItem(args, 0, PyLong_FromLong(nrows));
  PyTuple_SetItem(args, 1, PyLong_FromLong(ncols));
  PyTuple_SetItem(args, 2, PyLong_FromLong(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 title(const std::string &titlestr, const std::map<std::string, std::string> &keywords = {}) {
  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 = {}) {
  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) {
  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 xlabel(const std::string &str, const std::map<std::string, std::string> &keywords = {}) {
  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 = {}) {
  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 grid(bool flag) {
  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) {
  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() {
  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() {
  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() {
  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) {
  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) {
  PyObject *pyfilename = PyString_FromString(filename.c_str());
 
  PyObject *args = PyTuple_New(1);
  PyTuple_SetItem(args, 0, pyfilename);
 
  PyObject *res = PyObject_CallObject(detail::_interpreter::get().s_python_function_save, args);
  if (!res)
    throw std::runtime_error("Call to save() failed.");
 
  Py_DECREF(args);
  Py_DECREF(res);
}
 
inline void clf() {
  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 ion() {
  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 = {}) {
  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() {
  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) {
    // 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 = "") {
 
    assert(x.size() == y.size());
 
    PyObject *kwargs = PyDict_New();
    if (name != "")
      PyDict_SetItemString(kwargs, "label", PyString_FromString(name.c_str()));
 
    PyObject *xarray = get_array(x);
    PyObject *yarray = 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 = get_array(x);
      PyObject *yarray = 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