mirror of
https://github.com/pybind/pybind11.git
synced 2026-04-17 21:50:43 +00:00
Rename example20 -> example-numpy-dtypes
This commit is contained in:
Ivan Smirnov
195
example/example-numpy-dtypes.cpp
Normal file
195
example/example-numpy-dtypes.cpp
Normal file
@@ -0,0 +1,195 @@
|
||||
/*
|
||||
example/example-numpy-dtypes.cpp -- Structured and compound NumPy dtypes
|
||||
|
||||
Copyright (c) 2016 Ivan Smirnov
|
||||
|
||||
All rights reserved. Use of this source code is governed by a
|
||||
BSD-style license that can be found in the LICENSE file.
|
||||
*/
|
||||
|
||||
#include "example.h"
|
||||
|
||||
#include <pybind11/numpy.h>
|
||||
#include <cstdint>
|
||||
#include <iostream>
|
||||
|
||||
#ifdef __GNUC__
|
||||
#define PYBIND11_PACKED(cls) cls __attribute__((__packed__))
|
||||
#else
|
||||
#define PYBIND11_PACKED(cls) __pragma(pack(push, 1)) cls __pragma(pack(pop))
|
||||
#endif
|
||||
|
||||
namespace py = pybind11;
|
||||
|
||||
struct SimpleStruct {
|
||||
bool x;
|
||||
uint32_t y;
|
||||
float z;
|
||||
};
|
||||
|
||||
std::ostream& operator<<(std::ostream& os, const SimpleStruct& v) {
|
||||
return os << "s:" << v.x << "," << v.y << "," << v.z;
|
||||
}
|
||||
|
||||
PYBIND11_PACKED(struct PackedStruct {
|
||||
bool x;
|
||||
uint32_t y;
|
||||
float z;
|
||||
});
|
||||
|
||||
std::ostream& operator<<(std::ostream& os, const PackedStruct& v) {
|
||||
return os << "p:" << v.x << "," << v.y << "," << v.z;
|
||||
}
|
||||
|
||||
PYBIND11_PACKED(struct NestedStruct {
|
||||
SimpleStruct a;
|
||||
PackedStruct b;
|
||||
});
|
||||
|
||||
std::ostream& operator<<(std::ostream& os, const NestedStruct& v) {
|
||||
return os << "n:a=" << v.a << ";b=" << v.b;
|
||||
}
|
||||
|
||||
struct PartialStruct {
|
||||
bool x;
|
||||
uint32_t y;
|
||||
float z;
|
||||
long dummy2;
|
||||
};
|
||||
|
||||
struct PartialNestedStruct {
|
||||
long dummy1;
|
||||
PartialStruct a;
|
||||
long dummy2;
|
||||
};
|
||||
|
||||
struct UnboundStruct { };
|
||||
|
||||
struct StringStruct {
|
||||
char a[3];
|
||||
std::array<char, 3> b;
|
||||
};
|
||||
|
||||
std::ostream& operator<<(std::ostream& os, const StringStruct& v) {
|
||||
os << "a='";
|
||||
for (size_t i = 0; i < 3 && v.a[i]; i++) os << v.a[i];
|
||||
os << "',b='";
|
||||
for (size_t i = 0; i < 3 && v.b[i]; i++) os << v.b[i];
|
||||
return os << "'";
|
||||
}
|
||||
|
||||
template <typename T>
|
||||
py::array mkarray_via_buffer(size_t n) {
|
||||
return py::array(py::buffer_info(nullptr, sizeof(T),
|
||||
py::format_descriptor<T>::format(),
|
||||
1, { n }, { sizeof(T) }));
|
||||
}
|
||||
|
||||
template <typename S>
|
||||
py::array_t<S, 0> create_recarray(size_t n) {
|
||||
auto arr = mkarray_via_buffer<S>(n);
|
||||
auto req = arr.request();
|
||||
auto ptr = static_cast<S*>(req.ptr);
|
||||
for (size_t i = 0; i < n; i++) {
|
||||
ptr[i].x = i % 2; ptr[i].y = (uint32_t) i; ptr[i].z = (float) i * 1.5f;
|
||||
}
|
||||
return arr;
|
||||
}
|
||||
|
||||
std::string get_format_unbound() {
|
||||
return py::format_descriptor<UnboundStruct>::format();
|
||||
}
|
||||
|
||||
py::array_t<NestedStruct, 0> create_nested(size_t n) {
|
||||
auto arr = mkarray_via_buffer<NestedStruct>(n);
|
||||
auto req = arr.request();
|
||||
auto ptr = static_cast<NestedStruct*>(req.ptr);
|
||||
for (size_t i = 0; i < n; i++) {
|
||||
ptr[i].a.x = i % 2; ptr[i].a.y = (uint32_t) i; ptr[i].a.z = (float) i * 1.5f;
|
||||
ptr[i].b.x = (i + 1) % 2; ptr[i].b.y = (uint32_t) (i + 1); ptr[i].b.z = (float) (i + 1) * 1.5f;
|
||||
}
|
||||
return arr;
|
||||
}
|
||||
|
||||
py::array_t<PartialNestedStruct, 0> create_partial_nested(size_t n) {
|
||||
auto arr = mkarray_via_buffer<PartialNestedStruct>(n);
|
||||
auto req = arr.request();
|
||||
auto ptr = static_cast<PartialNestedStruct*>(req.ptr);
|
||||
for (size_t i = 0; i < n; i++) {
|
||||
ptr[i].a.x = i % 2; ptr[i].a.y = (uint32_t) i; ptr[i].a.z = (float) i * 1.5f;
|
||||
}
|
||||
return arr;
|
||||
}
|
||||
|
||||
py::array_t<StringStruct, 0> create_string_array(bool non_empty) {
|
||||
auto arr = mkarray_via_buffer<StringStruct>(non_empty ? 4 : 0);
|
||||
if (non_empty) {
|
||||
auto req = arr.request();
|
||||
auto ptr = static_cast<StringStruct*>(req.ptr);
|
||||
for (size_t i = 0; i < req.size * req.itemsize; i++)
|
||||
static_cast<char*>(req.ptr)[i] = 0;
|
||||
ptr[1].a[0] = 'a'; ptr[1].b[0] = 'a';
|
||||
ptr[2].a[0] = 'a'; ptr[2].b[0] = 'a';
|
||||
ptr[3].a[0] = 'a'; ptr[3].b[0] = 'a';
|
||||
|
||||
ptr[2].a[1] = 'b'; ptr[2].b[1] = 'b';
|
||||
ptr[3].a[1] = 'b'; ptr[3].b[1] = 'b';
|
||||
|
||||
ptr[3].a[2] = 'c'; ptr[3].b[2] = 'c';
|
||||
}
|
||||
return arr;
|
||||
}
|
||||
|
||||
template <typename S>
|
||||
void print_recarray(py::array_t<S, 0> arr) {
|
||||
auto req = arr.request();
|
||||
auto ptr = static_cast<S*>(req.ptr);
|
||||
for (size_t i = 0; i < req.size; i++)
|
||||
std::cout << ptr[i] << std::endl;
|
||||
}
|
||||
|
||||
void print_format_descriptors() {
|
||||
std::cout << py::format_descriptor<SimpleStruct>::format() << std::endl;
|
||||
std::cout << py::format_descriptor<PackedStruct>::format() << std::endl;
|
||||
std::cout << py::format_descriptor<NestedStruct>::format() << std::endl;
|
||||
std::cout << py::format_descriptor<PartialStruct>::format() << std::endl;
|
||||
std::cout << py::format_descriptor<PartialNestedStruct>::format() << std::endl;
|
||||
std::cout << py::format_descriptor<StringStruct>::format() << std::endl;
|
||||
}
|
||||
|
||||
void print_dtypes() {
|
||||
auto to_str = [](py::object obj) {
|
||||
return (std::string) (py::str) ((py::object) obj.attr("__str__"))();
|
||||
};
|
||||
std::cout << to_str(py::dtype_of<SimpleStruct>()) << std::endl;
|
||||
std::cout << to_str(py::dtype_of<PackedStruct>()) << std::endl;
|
||||
std::cout << to_str(py::dtype_of<NestedStruct>()) << std::endl;
|
||||
std::cout << to_str(py::dtype_of<PartialStruct>()) << std::endl;
|
||||
std::cout << to_str(py::dtype_of<PartialNestedStruct>()) << std::endl;
|
||||
std::cout << to_str(py::dtype_of<StringStruct>()) << std::endl;
|
||||
}
|
||||
|
||||
void init_ex_numpy_dtypes(py::module &m) {
|
||||
PYBIND11_NUMPY_DTYPE(SimpleStruct, x, y, z);
|
||||
PYBIND11_NUMPY_DTYPE(PackedStruct, x, y, z);
|
||||
PYBIND11_NUMPY_DTYPE(NestedStruct, a, b);
|
||||
PYBIND11_NUMPY_DTYPE(PartialStruct, x, y, z);
|
||||
PYBIND11_NUMPY_DTYPE(PartialNestedStruct, a);
|
||||
PYBIND11_NUMPY_DTYPE(StringStruct, a, b);
|
||||
|
||||
m.def("create_rec_simple", &create_recarray<SimpleStruct>);
|
||||
m.def("create_rec_packed", &create_recarray<PackedStruct>);
|
||||
m.def("create_rec_nested", &create_nested);
|
||||
m.def("create_rec_partial", &create_recarray<PartialStruct>);
|
||||
m.def("create_rec_partial_nested", &create_partial_nested);
|
||||
m.def("print_format_descriptors", &print_format_descriptors);
|
||||
m.def("print_rec_simple", &print_recarray<SimpleStruct>);
|
||||
m.def("print_rec_packed", &print_recarray<PackedStruct>);
|
||||
m.def("print_rec_nested", &print_recarray<NestedStruct>);
|
||||
m.def("print_dtypes", &print_dtypes);
|
||||
m.def("get_format_unbound", &get_format_unbound);
|
||||
m.def("create_string_array", &create_string_array);
|
||||
m.def("print_string_array", &print_recarray<StringStruct>);
|
||||
}
|
||||
|
||||
#undef PYBIND11_PACKED
|
||||
Reference in New Issue
Block a user