#pragma once

#include <vector>
#include <map>
#include <numeric>
#include <algorithm>
#include <stdexcept>
#include <iostream>
#include <stdint.h> // <cstdint> requires c++11 support

#if __cplusplus > 199711L || _MSC_VER > 1800
#  include <functional>
#endif

#include <Python.h>

#ifndef WITHOUT_NUMPY
#  define NPY_NO_DEPRECATED_API NPY_1_7_API_VERSION
#  include <numpy/arrayobject.h>
#endif // WITHOUT_NUMPY

#if PY_MAJOR_VERSION >= 3
#  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_plot;
            PyObject *s_python_function_semilogx;
            PyObject *s_python_function_semilogy;
            PyObject *s_python_function_loglog;
            PyObject *s_python_function_fill_between;
            PyObject *s_python_function_hist;
            PyObject *s_python_function_subplot;
            PyObject *s_python_function_legend;
            PyObject *s_python_function_xlim;
            PyObject *s_python_function_ion;
            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_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_empty_tuple;
            PyObject *s_python_function_stem;
            PyObject *s_python_function_xkcd;

            /* 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;
            }

        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* pylabname  = PyString_FromString("pylab");
                if (!pyplotname || !pylabname || !matplotlibname) {
                    throw std::runtime_error("couldnt create string");
                }

                PyObject* matplotlib = PyImport_Import(matplotlibname);
                Py_DECREF(matplotlibname);
                if (!matplotlib) { 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!"); }


                PyObject* pylabmod = PyImport_Import(pylabname);
                Py_DECREF(pylabname);
                if (!pylabmod) { throw std::runtime_error("Error loading module pylab!"); }

                s_python_function_show = PyObject_GetAttrString(pymod, "show");
                s_python_function_close = PyObject_GetAttrString(pymod, "close");
                s_python_function_draw = PyObject_GetAttrString(pymod, "draw");
                s_python_function_pause = PyObject_GetAttrString(pymod, "pause");
                s_python_function_figure = PyObject_GetAttrString(pymod, "figure");
                s_python_function_plot = PyObject_GetAttrString(pymod, "plot");
                s_python_function_semilogx = PyObject_GetAttrString(pymod, "semilogx");
                s_python_function_semilogy = PyObject_GetAttrString(pymod, "semilogy");
                s_python_function_loglog = PyObject_GetAttrString(pymod, "loglog");
                s_python_function_fill_between = PyObject_GetAttrString(pymod, "fill_between");
                s_python_function_hist = PyObject_GetAttrString(pymod,"hist");
                s_python_function_subplot = PyObject_GetAttrString(pymod, "subplot");
                s_python_function_legend = PyObject_GetAttrString(pymod, "legend");
                s_python_function_ylim = PyObject_GetAttrString(pymod, "ylim");
                s_python_function_title = PyObject_GetAttrString(pymod, "title");
                s_python_function_axis = PyObject_GetAttrString(pymod, "axis");
                s_python_function_xlabel = PyObject_GetAttrString(pymod, "xlabel");
                s_python_function_ylabel = PyObject_GetAttrString(pymod, "ylabel");
                s_python_function_grid = PyObject_GetAttrString(pymod, "grid");
                s_python_function_xlim = PyObject_GetAttrString(pymod, "xlim");
                s_python_function_ion = PyObject_GetAttrString(pymod, "ion");
                s_python_function_save = PyObject_GetAttrString(pylabmod, "savefig");
                s_python_function_annotate = PyObject_GetAttrString(pymod,"annotate");
                s_python_function_clf = PyObject_GetAttrString(pymod, "clf");
                s_python_function_errorbar = PyObject_GetAttrString(pymod, "errorbar");
                s_python_function_tight_layout = PyObject_GetAttrString(pymod, "tight_layout");
                s_python_function_stem = PyObject_GetAttrString(pymod, "stem");
                s_python_function_xkcd = PyObject_GetAttrString(pymod, "xkcd");

                if(    !s_python_function_show
                       || !s_python_function_close
                       || !s_python_function_draw
                       || !s_python_function_pause
                       || !s_python_function_figure
                       || !s_python_function_plot
                       || !s_python_function_semilogx
                       || !s_python_function_semilogy
                       || !s_python_function_loglog
                       || !s_python_function_fill_between
                       || !s_python_function_subplot
                       || !s_python_function_legend
                       || !s_python_function_ylim
                       || !s_python_function_title
                       || !s_python_function_axis
                       || !s_python_function_xlabel
                       || !s_python_function_ylabel
                       || !s_python_function_grid
                       || !s_python_function_xlim
                       || !s_python_function_ion
                       || !s_python_function_save
                       || !s_python_function_clf
                       || !s_python_function_annotate
                       || !s_python_function_errorbar
                       || !s_python_function_errorbar
                       || !s_python_function_tight_layout
                       || !s_python_function_stem
                       || !s_python_function_xkcd
                        ) { throw std::runtime_error("Couldn't find required function!"); }

                if (   !PyFunction_Check(s_python_function_show)
                       || !PyFunction_Check(s_python_function_close)
                       || !PyFunction_Check(s_python_function_draw)
                       || !PyFunction_Check(s_python_function_pause)
                       || !PyFunction_Check(s_python_function_figure)
                       || !PyFunction_Check(s_python_function_plot)
                       || !PyFunction_Check(s_python_function_semilogx)
                       || !PyFunction_Check(s_python_function_semilogy)
                       || !PyFunction_Check(s_python_function_loglog)
                       || !PyFunction_Check(s_python_function_fill_between)
                       || !PyFunction_Check(s_python_function_subplot)
                       || !PyFunction_Check(s_python_function_legend)
                       || !PyFunction_Check(s_python_function_annotate)
                       || !PyFunction_Check(s_python_function_ylim)
                       || !PyFunction_Check(s_python_function_title)
                       || !PyFunction_Check(s_python_function_axis)
                       || !PyFunction_Check(s_python_function_xlabel)
                       || !PyFunction_Check(s_python_function_ylabel)
                       || !PyFunction_Check(s_python_function_grid)
                       || !PyFunction_Check(s_python_function_xlim)
                       || !PyFunction_Check(s_python_function_ion)
                       || !PyFunction_Check(s_python_function_save)
                       || !PyFunction_Check(s_python_function_clf)
                       || !PyFunction_Check(s_python_function_tight_layout)
                       || !PyFunction_Check(s_python_function_errorbar)
                       || !PyFunction_Check(s_python_function_stem)
                       || !PyFunction_Check(s_python_function_xkcd)
                        ) { throw std::runtime_error("Python object is unexpectedly not a PyFunction."); }

                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;
    }

#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>
    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_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)
    {

        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));


        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 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>
    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::string &s = "")
    {
        assert(x.size() == y.size());

        PyObject* xarray = get_array(x);
        PyObject* yarray = get_array(y);
        PyObject* yerrarray = get_array(yerr);

        PyObject *kwargs = PyDict_New();

        PyDict_SetItemString(kwargs, "yerr", yerrarray);

        PyObject *pystring = PyString_FromString(s.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_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 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);
    }

    inline void figure()
    {
        PyObject* res = PyObject_CallObject(detail::_interpreter::get().s_python_function_figure, detail::_interpreter::get().s_python_empty_tuple);
        if(!res) throw std::runtime_error("Call to figure() 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;
    }

    inline void subplot(long nrows, long ncols, long plot_number)
    {
        // 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 title(const std::string &titlestr)
    {
        PyObject* pytitlestr = PyString_FromString(titlestr.c_str());
        PyObject* args = PyTuple_New(1);
        PyTuple_SetItem(args, 0, pytitlestr);

        PyObject* res = PyObject_CallObject(detail::_interpreter::get().s_python_function_title, args);
        if(!res) throw std::runtime_error("Call to title() failed.");

        Py_DECREF(args);
        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)
    {
        PyObject* pystr = PyString_FromString(str.c_str());
        PyObject* args = PyTuple_New(1);
        PyTuple_SetItem(args, 0, pystr);

        PyObject* res = PyObject_CallObject(detail::_interpreter::get().s_python_function_xlabel, args);
        if(!res) throw std::runtime_error("Call to xlabel() failed.");

        Py_DECREF(args);
        Py_DECREF(res);
    }

    inline void ylabel(const std::string &str)
    {
        PyObject* pystr = PyString_FromString(str.c_str());
        PyObject* args = PyTuple_New(1);
        PyTuple_SetItem(args, 0, pystr);

        PyObject* res = PyObject_CallObject(detail::_interpreter::get().s_python_function_ylabel, args);
        if(!res) throw std::runtime_error("Call to ylabel() failed.");

        Py_DECREF(args);
        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);
    }

// 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);
    }

#if __cplusplus > 199711L || _MSC_VER > 1800
// C++11-exclusive content starts here (variadic plot() and initializer list support)

    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::distance;
                using std::begin;
                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);
    }

#endif

} // end namespace matplotlibcpp
