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7bdd74a9fb
pybind11/include/pybind11/numpy.h
Ivan Smirnov 7bdd74a9fb Fix PYBIND11_DTYPE to work with MSVC compiler
2016-08-13 12:43:16 +01:00

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/*
pybind11/numpy.h: Basic NumPy support, vectorize() wrapper
Copyright (c) 2016 Wenzel Jakob <wenzel.jakob@epfl.ch>
All rights reserved. Use of this source code is governed by a
BSD-style license that can be found in the LICENSE file.
*/
#pragma once
#include "pybind11.h"
#include "complex.h"
#include <numeric>
#include <algorithm>
#include <cstdlib>
#include <cstring>
#include <initializer_list>
#if defined(_MSC_VER)
#pragma warning(push)
#pragma warning(disable: 4127) // warning C4127: Conditional expression is constant
#endif
NAMESPACE_BEGIN(pybind11)
namespace detail {
template <typename type, typename SFINAE = void> struct npy_format_descriptor { };
template <typename T>
struct is_pod_struct {
enum { value = std::is_pod<T>::value && // offsetof only works correctly for POD types
!std::is_integral<T>::value &&
!std::is_same<T, float>::value &&
!std::is_same<T, bool>::value &&
!std::is_same<T, std::complex<float>>::value &&
!std::is_same<T, std::complex<double>>::value };
};
}
class array : public buffer {
public:
struct API {
enum Entries {
API_PyArray_Type = 2,
API_PyArray_DescrFromType = 45,
API_PyArray_FromAny = 69,
API_PyArray_NewCopy = 85,
API_PyArray_NewFromDescr = 94,
API_PyArray_DescrConverter = 174,
API_PyArray_GetArrayParamsFromObject = 278,
NPY_C_CONTIGUOUS_ = 0x0001,
NPY_F_CONTIGUOUS_ = 0x0002,
NPY_ARRAY_FORCECAST_ = 0x0010,
NPY_ENSURE_ARRAY_ = 0x0040,
NPY_BOOL_ = 0,
NPY_BYTE_, NPY_UBYTE_,
NPY_SHORT_, NPY_USHORT_,
NPY_INT_, NPY_UINT_,
NPY_LONG_, NPY_ULONG_,
NPY_LONGLONG_, NPY_ULONGLONG_,
NPY_FLOAT_, NPY_DOUBLE_, NPY_LONGDOUBLE_,
NPY_CFLOAT_, NPY_CDOUBLE_, NPY_CLONGDOUBLE_
};
static API lookup() {
module m = module::import("numpy.core.multiarray");
object c = (object) m.attr("_ARRAY_API");
#if PY_MAJOR_VERSION >= 3
void **api_ptr = (void **) (c ? PyCapsule_GetPointer(c.ptr(), NULL) : nullptr);
#else
void **api_ptr = (void **) (c ? PyCObject_AsVoidPtr(c.ptr()) : nullptr);
#endif
API api;
#define DECL_NPY_API(Func) api.Func##_ = (decltype(api.Func##_)) api_ptr[API_##Func];
DECL_NPY_API(PyArray_Type);
DECL_NPY_API(PyArray_DescrFromType);
DECL_NPY_API(PyArray_FromAny);
DECL_NPY_API(PyArray_NewCopy);
DECL_NPY_API(PyArray_NewFromDescr);
DECL_NPY_API(PyArray_DescrConverter);
DECL_NPY_API(PyArray_GetArrayParamsFromObject);
#undef DECL_NPY_API
return api;
}
bool PyArray_Check_(PyObject *obj) const { return (bool) PyObject_TypeCheck(obj, PyArray_Type_); }
PyObject *(*PyArray_DescrFromType_)(int);
PyObject *(*PyArray_NewFromDescr_)
(PyTypeObject *, PyObject *, int, Py_intptr_t *,
Py_intptr_t *, void *, int, PyObject *);
PyObject *(*PyArray_NewCopy_)(PyObject *, int);
PyTypeObject *PyArray_Type_;
PyObject *(*PyArray_FromAny_) (PyObject *, PyObject *, int, int, int, PyObject *);
int (*PyArray_DescrConverter_) (PyObject *, PyObject **);
int (*PyArray_GetArrayParamsFromObject_)(PyObject *, PyObject *, char, PyObject **, int *,
Py_ssize_t *, PyObject **, PyObject *);
};
PYBIND11_OBJECT_DEFAULT(array, buffer, lookup_api().PyArray_Check_)
enum {
c_style = API::NPY_C_CONTIGUOUS_,
f_style = API::NPY_F_CONTIGUOUS_,
forcecast = API::NPY_ARRAY_FORCECAST_
};
template <typename Type> array(size_t size, const Type *ptr) {
API& api = lookup_api();
PyObject *descr = detail::npy_format_descriptor<Type>::dtype().release().ptr();
Py_intptr_t shape = (Py_intptr_t) size;
object tmp = object(api.PyArray_NewFromDescr_(
api.PyArray_Type_, descr, 1, &shape, nullptr, (void *) ptr, 0, nullptr), false);
if (ptr && tmp)
tmp = object(api.PyArray_NewCopy_(tmp.ptr(), -1 /* any order */), false);
if (!tmp)
pybind11_fail("NumPy: unable to create array!");
m_ptr = tmp.release().ptr();
}
array(const buffer_info &info) {
PyObject *arr = nullptr, *descr = nullptr;
int ndim = 0;
Py_ssize_t dims[32];
// allocate zeroed memory if it hasn't been provided
auto buf_info = info;
if (!buf_info.ptr)
buf_info.ptr = std::calloc(info.size, info.itemsize);
if (!buf_info.ptr)
pybind11_fail("NumPy: failed to allocate memory for buffer");
auto view = memoryview(buf_info);
API& api = lookup_api();
auto res = api.PyArray_GetArrayParamsFromObject_(view.ptr(), nullptr, 1, &descr,
&ndim, dims, &arr, nullptr);
if (res < 0 || !arr || descr)
pybind11_fail("NumPy: unable to convert buffer to an array");
m_ptr = arr;
}
protected:
static API &lookup_api() {
static API api = API::lookup();
return api;
}
template <typename T, typename SFINAE> friend struct detail::npy_format_descriptor;
};
template <typename T, int ExtraFlags = array::forcecast> class array_t : public array {
public:
PYBIND11_OBJECT_CVT(array_t, array, is_non_null, m_ptr = ensure(m_ptr));
array_t() : array() { }
array_t(const buffer_info& info) : array(info) {}
static bool is_non_null(PyObject *ptr) { return ptr != nullptr; }
static PyObject *ensure(PyObject *ptr) {
if (ptr == nullptr)
return nullptr;
API &api = lookup_api();
PyObject *descr = detail::npy_format_descriptor<T>::dtype().release().ptr();
PyObject *result = api.PyArray_FromAny_(ptr, descr, 0, 0, API::NPY_ENSURE_ARRAY_ | ExtraFlags, nullptr);
if (!result)
PyErr_Clear();
Py_DECREF(ptr);
return result;
}
};
template <typename T>
struct format_descriptor<T, typename std::enable_if<detail::is_pod_struct<T>::value>::type> {
static const char *format() {
return detail::npy_format_descriptor<T>::format();
}
};
template <typename T>
object dtype_of() {
return detail::npy_format_descriptor<T>::dtype();
}
NAMESPACE_BEGIN(detail)
template <typename T> struct npy_format_descriptor<T, typename std::enable_if<std::is_integral<T>::value>::type> {
private:
constexpr static const int values[8] = {
array::API::NPY_BYTE_, array::API::NPY_UBYTE_, array::API::NPY_SHORT_, array::API::NPY_USHORT_,
array::API::NPY_INT_, array::API::NPY_UINT_, array::API::NPY_LONGLONG_, array::API::NPY_ULONGLONG_ };
public:
enum { value = values[detail::log2(sizeof(T)) * 2 + (std::is_unsigned<T>::value ? 1 : 0)] };
static object dtype() {
if (auto ptr = array::lookup_api().PyArray_DescrFromType_(value))
return object(ptr, true);
pybind11_fail("Unsupported buffer format!");
}
template <typename T2 = T, typename std::enable_if<std::is_signed<T2>::value, int>::type = 0>
static PYBIND11_DESCR name() { return _("int") + _<sizeof(T)*8>(); }
template <typename T2 = T, typename std::enable_if<!std::is_signed<T2>::value, int>::type = 0>
static PYBIND11_DESCR name() { return _("uint") + _<sizeof(T)*8>(); }
};
template <typename T> constexpr const int npy_format_descriptor<
T, typename std::enable_if<std::is_integral<T>::value>::type>::values[8];
#define DECL_FMT(Type, NumPyName, Name) template<> struct npy_format_descriptor<Type> { \
enum { value = array::API::NumPyName }; \
static object dtype() { \
if (auto ptr = array::lookup_api().PyArray_DescrFromType_(value)) \
return object(ptr, true); \
pybind11_fail("Unsupported buffer format!"); \
} \
static PYBIND11_DESCR name() { return _(Name); } }
DECL_FMT(float, NPY_FLOAT_, "float32");
DECL_FMT(double, NPY_DOUBLE_, "float64");
DECL_FMT(bool, NPY_BOOL_, "bool");
DECL_FMT(std::complex<float>, NPY_CFLOAT_, "complex64");
DECL_FMT(std::complex<double>, NPY_CDOUBLE_, "complex128");
#undef DECL_FMT
struct field_descriptor {
const char *name;
int offset;
object descr;
};
template <typename T>
struct npy_format_descriptor<T, typename std::enable_if<is_pod_struct<T>::value>::type> {
static PYBIND11_DESCR name() { return _("user-defined"); }
static object dtype() {
if (!dtype_())
pybind11_fail("NumPy: unsupported buffer format!");
return object(dtype_(), true);
}
static const char* format() {
if (!dtype_())
pybind11_fail("NumPy: unsupported buffer format!");
return format_();
}
static void register_dtype(std::initializer_list<field_descriptor> fields) {
array::API& api = array::lookup_api();
auto args = dict();
list names { }, offsets { }, formats { };
for (auto field : fields) {
if (!field.descr)
pybind11_fail("NumPy: unsupported field dtype");
names.append(str(field.name));
offsets.append(int_(field.offset));
formats.append(field.descr);
}
args["names"] = names;
args["offsets"] = offsets;
args["formats"] = formats;
if (!api.PyArray_DescrConverter_(args.release().ptr(), &dtype_()) || !dtype_())
pybind11_fail("NumPy: failed to create structured dtype");
auto np = module::import("numpy");
auto empty = (object) np.attr("empty");
if (auto arr = (object) empty(int_(0), dtype()))
if (auto view = PyMemoryView_FromObject(arr.ptr()))
if (auto info = PyMemoryView_GET_BUFFER(view)) {
std::strncpy(format_(), info->format, 4096);
return;
}
pybind11_fail("NumPy: failed to extract buffer format");
}
private:
static inline PyObject*& dtype_() { static PyObject *ptr = nullptr; return ptr; }
static inline char* format_() { static char s[4096]; return s; }
};
#define PB11_IMPL_FIELD_DESCRIPTOR(Type, Field) \
::pybind11::detail::field_descriptor { \
#Field, offsetof(Type, Field), \
::pybind11::detail::npy_format_descriptor<decltype(static_cast<Type*>(0)->Field)>::dtype() \
}
// The main idea of this macro is borrowed from https://github.com/swansontec/map-macro
// (C) William Swanson, Paul Fultz
#define PB11_IMPL_EVAL0(...) __VA_ARGS__
#define PB11_IMPL_EVAL1(...) PB11_IMPL_EVAL0 (PB11_IMPL_EVAL0 (PB11_IMPL_EVAL0 (__VA_ARGS__)))
#define PB11_IMPL_EVAL2(...) PB11_IMPL_EVAL1 (PB11_IMPL_EVAL1 (PB11_IMPL_EVAL1 (__VA_ARGS__)))
#define PB11_IMPL_EVAL3(...) PB11_IMPL_EVAL2 (PB11_IMPL_EVAL2 (PB11_IMPL_EVAL2 (__VA_ARGS__)))
#define PB11_IMPL_EVAL4(...) PB11_IMPL_EVAL3 (PB11_IMPL_EVAL3 (PB11_IMPL_EVAL3 (__VA_ARGS__)))
#define PB11_IMPL_EVAL(...) PB11_IMPL_EVAL4 (PB11_IMPL_EVAL4 (PB11_IMPL_EVAL4 (__VA_ARGS__)))
#define PB11_IMPL_MAP_END(...)
#define PB11_IMPL_MAP_OUT
#define PB11_IMPL_MAP_COMMA ,
#define PB11_IMPL_MAP_GET_END() 0, PB11_IMPL_MAP_END
#define PB11_IMPL_MAP_NEXT0(test, next, ...) next PB11_IMPL_MAP_OUT
#define PB11_IMPL_MAP_NEXT1(test, next) PB11_IMPL_MAP_NEXT0 (test, next, 0)
#define PB11_IMPL_MAP_NEXT(test, next) PB11_IMPL_MAP_NEXT1 (PB11_IMPL_MAP_GET_END test, next)
#ifdef _MSC_VER
#define PB11_IMPL_MAP_LIST_NEXT1(test, next) \
PB11_IMPL_EVAL0 (PB11_IMPL_MAP_NEXT0 (test, PB11_IMPL_MAP_COMMA next, 0))
#else
#define PB11_IMPL_MAP_LIST_NEXT1(test, next) \
PB11_IMPL_MAP_NEXT0 (test, PB11_IMPL_MAP_COMMA next, 0)
#endif
#define PB11_IMPL_MAP_LIST_NEXT(test, next) \
PB11_IMPL_MAP_LIST_NEXT1 (PB11_IMPL_MAP_GET_END test, next)
#define PB11_IMPL_MAP_LIST0(f, t, x, peek, ...) \
f(t, x) PB11_IMPL_MAP_LIST_NEXT (peek, PB11_IMPL_MAP_LIST1) (f, t, peek, __VA_ARGS__)
#define PB11_IMPL_MAP_LIST1(f, t, x, peek, ...) \
f(t, x) PB11_IMPL_MAP_LIST_NEXT (peek, PB11_IMPL_MAP_LIST0) (f, t, peek, __VA_ARGS__)
#define PB11_IMPL_MAP_LIST(f, t, ...) PB11_IMPL_EVAL (PB11_IMPL_MAP_LIST1 (f, t, __VA_ARGS__, (), 0))
#define PYBIND11_DTYPE(Type, ...) \
::pybind11::detail::npy_format_descriptor<Type>::register_dtype \
({PB11_IMPL_MAP_LIST(PB11_IMPL_FIELD_DESCRIPTOR, Type, __VA_ARGS__)})
template <class T>
using array_iterator = typename std::add_pointer<T>::type;
template <class T>
array_iterator<T> array_begin(const buffer_info& buffer) {
return array_iterator<T>(reinterpret_cast<T*>(buffer.ptr));
}
template <class T>
array_iterator<T> array_end(const buffer_info& buffer) {
return array_iterator<T>(reinterpret_cast<T*>(buffer.ptr) + buffer.size);
}
class common_iterator {
public:
using container_type = std::vector<size_t>;
using value_type = container_type::value_type;
using size_type = container_type::size_type;
common_iterator() : p_ptr(0), m_strides() {}
common_iterator(void* ptr, const container_type& strides, const std::vector<size_t>& shape)
: p_ptr(reinterpret_cast<char*>(ptr)), m_strides(strides.size()) {
m_strides.back() = static_cast<value_type>(strides.back());
for (size_type i = m_strides.size() - 1; i != 0; --i) {
size_type j = i - 1;
value_type s = static_cast<value_type>(shape[i]);
m_strides[j] = strides[j] + m_strides[i] - strides[i] * s;
}
}
void increment(size_type dim) {
p_ptr += m_strides[dim];
}
void* data() const {
return p_ptr;
}
private:
char* p_ptr;
container_type m_strides;
};
template <size_t N> class multi_array_iterator {
public:
using container_type = std::vector<size_t>;
multi_array_iterator(const std::array<buffer_info, N> &buffers,
const std::vector<size_t> &shape)
: m_shape(shape.size()), m_index(shape.size(), 0),
m_common_iterator() {
// Manual copy to avoid conversion warning if using std::copy
for (size_t i = 0; i < shape.size(); ++i)
m_shape[i] = static_cast<container_type::value_type>(shape[i]);
container_type strides(shape.size());
for (size_t i = 0; i < N; ++i)
init_common_iterator(buffers[i], shape, m_common_iterator[i], strides);
}
multi_array_iterator& operator++() {
for (size_t j = m_index.size(); j != 0; --j) {
size_t i = j - 1;
if (++m_index[i] != m_shape[i]) {
increment_common_iterator(i);
break;
} else {
m_index[i] = 0;
}
}
return *this;
}
template <size_t K, class T> const T& data() const {
return *reinterpret_cast<T*>(m_common_iterator[K].data());
}
private:
using common_iter = common_iterator;
void init_common_iterator(const buffer_info &buffer,
const std::vector<size_t> &shape,
common_iter &iterator, container_type &strides) {
auto buffer_shape_iter = buffer.shape.rbegin();
auto buffer_strides_iter = buffer.strides.rbegin();
auto shape_iter = shape.rbegin();
auto strides_iter = strides.rbegin();
while (buffer_shape_iter != buffer.shape.rend()) {
if (*shape_iter == *buffer_shape_iter)
*strides_iter = static_cast<size_t>(*buffer_strides_iter);
else
*strides_iter = 0;
++buffer_shape_iter;
++buffer_strides_iter;
++shape_iter;
++strides_iter;
}
std::fill(strides_iter, strides.rend(), 0);
iterator = common_iter(buffer.ptr, strides, shape);
}
void increment_common_iterator(size_t dim) {
for (auto &iter : m_common_iterator)
iter.increment(dim);
}
container_type m_shape;
container_type m_index;
std::array<common_iter, N> m_common_iterator;
};
template <size_t N>
bool broadcast(const std::array<buffer_info, N>& buffers, size_t& ndim, std::vector<size_t>& shape) {
ndim = std::accumulate(buffers.begin(), buffers.end(), size_t(0), [](size_t res, const buffer_info& buf) {
return std::max(res, buf.ndim);
});
shape = std::vector<size_t>(ndim, 1);
bool trivial_broadcast = true;
for (size_t i = 0; i < N; ++i) {
auto res_iter = shape.rbegin();
bool i_trivial_broadcast = (buffers[i].size == 1) || (buffers[i].ndim == ndim);
for (auto shape_iter = buffers[i].shape.rbegin();
shape_iter != buffers[i].shape.rend(); ++shape_iter, ++res_iter) {
if (*res_iter == 1)
*res_iter = *shape_iter;
else if ((*shape_iter != 1) && (*res_iter != *shape_iter))
pybind11_fail("pybind11::vectorize: incompatible size/dimension of inputs!");
i_trivial_broadcast = i_trivial_broadcast && (*res_iter == *shape_iter);
}
trivial_broadcast = trivial_broadcast && i_trivial_broadcast;
}
return trivial_broadcast;
}
template <typename Func, typename Return, typename... Args>
struct vectorize_helper {
typename std::remove_reference<Func>::type f;
template <typename T>
vectorize_helper(T&&f) : f(std::forward<T>(f)) { }
object operator()(array_t<Args, array::c_style | array::forcecast>... args) {
return run(args..., typename make_index_sequence<sizeof...(Args)>::type());
}
template <size_t ... Index> object run(array_t<Args, array::c_style | array::forcecast>&... args, index_sequence<Index...> index) {
/* Request buffers from all parameters */
const size_t N = sizeof...(Args);
std::array<buffer_info, N> buffers {{ args.request()... }};
/* Determine dimensions parameters of output array */
size_t ndim = 0;
std::vector<size_t> shape(0);
bool trivial_broadcast = broadcast(buffers, ndim, shape);
size_t size = 1;
std::vector<size_t> strides(ndim);
if (ndim > 0) {
strides[ndim-1] = sizeof(Return);
for (size_t i = ndim - 1; i > 0; --i) {
strides[i - 1] = strides[i] * shape[i];
size *= shape[i];
}
size *= shape[0];
}
if (size == 1)
return cast(f(*((Args *) buffers[Index].ptr)...));
array result(buffer_info(nullptr, sizeof(Return),
format_descriptor<Return>::format(),
ndim, shape, strides));
buffer_info buf = result.request();
Return *output = (Return *) buf.ptr;
if (trivial_broadcast) {
/* Call the function */
for (size_t i=0; i<size; ++i) {
output[i] = f((buffers[Index].size == 1
? *((Args *) buffers[Index].ptr)
: ((Args *) buffers[Index].ptr)[i])...);
}
} else {
apply_broadcast<N, Index...>(buffers, buf, index);
}
return result;
}
template <size_t N, size_t... Index>
void apply_broadcast(const std::array<buffer_info, N> &buffers,
buffer_info &output, index_sequence<Index...>) {
using input_iterator = multi_array_iterator<N>;
using output_iterator = array_iterator<Return>;
input_iterator input_iter(buffers, output.shape);
output_iterator output_end = array_end<Return>(output);
for (output_iterator iter = array_begin<Return>(output);
iter != output_end; ++iter, ++input_iter) {
*iter = f((input_iter.template data<Index, Args>())...);
}
}
};
template <typename T, int Flags> struct handle_type_name<array_t<T, Flags>> {
static PYBIND11_DESCR name() { return _("numpy.ndarray[") + type_caster<T>::name() + _("]"); }
};
NAMESPACE_END(detail)
template <typename Func, typename Return, typename... Args>
detail::vectorize_helper<Func, Return, Args...> vectorize(const Func &f, Return (*) (Args ...)) {
return detail::vectorize_helper<Func, Return, Args...>(f);
}
template <typename Return, typename... Args>
detail::vectorize_helper<Return (*) (Args ...), Return, Args...> vectorize(Return (*f) (Args ...)) {
return vectorize<Return (*) (Args ...), Return, Args...>(f, f);
}
template <typename func> auto vectorize(func &&f) -> decltype(
vectorize(std::forward<func>(f), (typename detail::remove_class<decltype(&std::remove_reference<func>::type::operator())>::type *) nullptr)) {
return vectorize(std::forward<func>(f), (typename detail::remove_class<decltype(
&std::remove_reference<func>::type::operator())>::type *) nullptr);
}
NAMESPACE_END(pybind11)
#if defined(_MSC_VER)
#pragma warning(pop)
#endif
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