yohhoy’s gists

yohhoy / submdspan-test.cpp

Created January 31, 2024 14:19

submdspan

	#include <cassert>
	#include <concepts>
	#include <span>
	#include <tuple>
	#include <utility>
	#include <ranges>
	#if 1
	#include <https://raw.githubusercontent.com/kokkos/mdspan/single-header/mdspan.hpp>
	#else
	#include <mdspan>

yohhoy / mdspan_hilbert.cpp

Last active November 25, 2023 17:07

Hilbert curve layout for std::mdspan

	#include <cassert>
	#include <bit>
	#include <iostream>
	#include <utility>
	#if 1
	#include <https://raw.githubusercontent.com/kokkos/mdspan/single-header/mdspan.hpp>
	using std::experimental::mdspan;
	using std::experimental::dextents;
	#else
	#include <mdspan>

yohhoy / mdspan-test.cpp

Last active May 2, 2024 07:22

mdspan constructors & deduction guides

	#include <cassert>
	#include <array>
	#include <span>
	#include <type_traits>
	#if 0
	#include <mdspan>
	#else
	#include <https://raw.githubusercontent.com/kokkos/mdspan/single-header/mdspan.hpp>
	#endif
	using namespace std;

yohhoy / mm.c

Last active September 22, 2022 04:44

	// https://groups.google.com/g/golang-nuts/c/Gze1TRtdLdc/m/RoD2AxssDgAJ
	// http://svr-pes20-cppmem.cl.cam.ac.uk/cppmem/
	int main() {
	int x = 0;
	atomic_int int y = 0;
	{{{ { x = 1;
	y.store(1);
	x = 1;
	y.store(1); }
	\|\|\| { y.load().readsvalue(0);

yohhoy / barrier.md

Created August 29, 2022 07:13

Full barrier

P: =p0=\ /----\ /=p1=\ /----\ /=
        *      *      *      *
C: ----/ \=c0=/ \----/ \=c1=/ \-

Half barrier

P: p0=\--------/=p1=\--------/=

yohhoy / chrono_io.hpp

Last active December 15, 2021 04:38

Ad-hoc std::ostream support for <chrono>

	#include <ctime>
	#include <chrono>
	#include <iostream>
	#include <iomanip>

	namespace std {

	// https://timsong-cpp.github.io/cppwp/n4868/time.cal.ymd.nonmembers#14
	// "yyyy-mm-dd"
	inline ostream& operator<<(ostream& os, const chrono::year_month_day& ymd) {

yohhoy / endian.hpp

Last active October 28, 2021 10:16

endian conversion

	// requires C++23 or later
	#include <bit>
	#include <concepts>

	template <std::integral T>
	constexpr T hton(T value) noexcept
	{
	if constexpr (std::endian::native == std::endian::little) {
	return std::byteswap(value);
	} else {

yohhoy / cv2ff.cpp

Created August 4, 2021 16:27

Convert from OpenCV image and write movie with FFmpeg (OpenCV 4.5, FFmpeg 4.4)

	/*
	* Convert from OpenCV image and write movie with FFmpeg
	*
	* Copyright (c) 2021 yohhoy
	*/
	#include <iostream>
	#include <vector>
	// FFmpeg
	extern "C" {
	#include <libavformat/avformat.h>

yohhoy / pre-p2210r2.cpp

Created June 25, 2021 08:20

	#include <algorithm>
	#include <iostream>
	#include <string>
	#include <string_view>
	#include <ranges>

	int main() {
	std::string_view str = "apple,banana,cinnamon";
	for (auto rev_item: str \| std::views::reverse \| std::views::split(',')) {
	static_assert( std::ranges::forward_range<decltype(rev_item)>);

yohhoy / error-concepts-diagnostics.log

Last active June 25, 2021 02:42

	prog.cc: In function 'int main()':
	prog.cc:6:19: error: no match for 'operator\|' (operand types are 'std::forward_list<int, std::allocator<int> >' and 'const std::ranges::views::_Reverse')
	6 \| for (int _: lst \| std::views::reverse) {}
	\| ~~~ ^ ~~~~~~~~~~~~~~~~~~~
	\| \| \|
	\| \| const std::ranges::views::_Reverse
	\| std::forward_list<int, std::allocator<int> >
	In file included from prog.cc:2:
	/opt/wandbox/gcc-head/include/c++/12.0.0/ranges:818:7: note: candidate: 'template<class _Lhs, class _Rhs> requires (derived_from<_Lhs, std::ranges::views::__adaptor::_RangeAdaptorClosure>) && (derived_from<_Rhs, std::ranges::views::__adaptor::_RangeAdaptorClosure>) constexpr auto std::ranges::views::__adaptor::operator\|(_Lhs, _Rhs)'
	818 \| operator\|(_Lhs __lhs, _Rhs __rhs)

	prog.cc: In function 'int main()':
	prog.cc:6:19: error: no match for 'operator\|' (operand types are 'std::forward_list<int, std::allocator<int> >' and 'const std::ranges::views::_Reverse')
	6 \| for (int _: lst \| std::views::reverse) {}
	\| ~~~ ^ ~~~~~~~~~~~~~~~~~~~
	\| \| \|
	\| \| const std::ranges::views::_Reverse
	\| std::forward_list<int, std::allocator<int> >
	In file included from prog.cc:2:
	/opt/wandbox/gcc-head/include/c++/12.0.0/ranges:818:7: note: candidate: 'template<class _Lhs, class _Rhs> requires (derived_from<_Lhs, std::ranges::views::__adaptor::_RangeAdaptorClosure>) && (derived_from<_Rhs, std::ranges::views::__adaptor::_RangeAdaptorClosure>) constexpr auto std::ranges::views::__adaptor::operator\|(_Lhs, _Rhs)'
	818 \| operator\|(_Lhs __lhs, _Rhs __rhs)

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