gpt4 book ai didi

c++ - CUDA 推力 zip_iterator 元组 transform_reduce

转载 作者:塔克拉玛干 更新时间:2023-11-03 00:38:22 26 4
gpt4 key购买 nike

我想计算 \left | \vec{a} - \vec{b} \right |用于载体 \vec{a}\vec{b} , 其中\left | \vec{x} \right |表示 vector 的大小 \vec{x} .由于这涉及对两个 vector 的每个对应分量之间的差的平方和求平方根,因此它应该是一个高度可并行化的任务。我在 Windows 10 上通过 Cygwin 使用 Cuda 和 Thrust。Cuda 和 Thrust 都正常工作。

下面的代码编译并运行(使用 nvcc),但这只是因为我在 main 的底部注释掉了三行,我认为每一行都应该工作但没有。 func::operator()(tup t) 认为我传递给它的参数实际上不是 tup 类型。

为了使其更有可能至少编译,我还注释掉了运算符的实际主体。运算符应该找到输入 tup 的元素之间的平方差。 transform_reduce(在本例中为 func())的归约 unary_op 将添加这些,得到差值的范数平方 vector 。

#include <iostream>
#include <stdlib.h>
#include <thrust/device_vector.h>
#include <thrust/transform.h>
#include <thrust/tuple.h>
#include <thrust/transform_reduce.h>
#include <thrust/iterator/zip_iterator.h>

typedef thrust::device_vector<float> dvec;
typedef dvec::iterator iter;
typedef thrust::tuple<iter, iter> tup;

struct func: public thrust::unary_function<tup, float>
{
__device__ float operator()(tup t) //difsq
{
// I've commented out these two lines for testing purposes:
// float f = thrust::get<0>(t) - thrust::get<1>(t);
// return f*f;
return 3.14;
}
};

int main()
{
dvec a(40, 4.f);
dvec b(40, 3.f);
auto begin = thrust::make_zip_iterator(thrust::make_tuple(a.begin(), b.begin()));
auto end = thrust::make_zip_iterator(thrust::make_tuple(a.end(), b.end()));

//these two lines work
thrust::get<0>(begin[0]);
std::cout << thrust::get<0>(begin[0]) - thrust::get<1>(begin[0]);


//these three lines do not
//thrust::transform_reduce(begin, end, func(), 0.0f, thrust::plus<float>());
//func()(begin[0]);
//thrust::transform(begin, end, begin, func());


std::cout << "done" << std::endl;
return 0;
}

我收到此错误:(我的程序名为 sandbox.cu)

C:\Program Files\NVIDIA GPU Computing Toolkit\CUDA\v7.5\bin/../include\thrust/detail/tuple.inl(310): error: no instance of constructor "thrust::detail::normal_iterator<Pointer>::normal_iterator [with Pointer=thrust::device_ptr<float>]" matches the argument list
argument types are: (const thrust::device_reference<float>)
detected during:
instantiation of "thrust::detail::cons<HT, TT>::cons(const thrust::detail::cons<HT2, TT2> &) [with HT=iter, TT=thrust::detail::cons<iter, thrust::null_type>, HT2=thrust::device_reference<float>, TT2=thrust::detail::cons<thrust::device_reference<float>, thrust::null_type>]"
C:\Program Files\NVIDIA GPU Computing Toolkit\CUDA\v7.5\bin/../include\thrust/tuple.h(361): here
instantiation of "thrust::tuple<T0, T1, T2, T3, T4, T5, T6, T7, T8, T9>::tuple(const thrust::detail::cons<U1, U2> &) [with T0=iter, T1=iter, T2=thrust::null_type, T3=thrust::null_type, T4=thrust::null_type, T5=thrust::null_type, T6=thrust::null_type, T7=thrust::null_type, T8=thrust::null_type, T9=thrust::null_type, U1=thrust::device_reference<float>, U2=thrust::detail::cons<thrust::device_reference<float>, thrust::null_type>]"
sandbox.cu(37): here

C:\Program Files\NVIDIA GPU Computing Toolkit\CUDA\v7.5\bin/../include\thrust/detail/tuple.inl(411): error: no instance of constructor "thrust::detail::normal_iterator<Pointer>::normal_iterator [with Pointer=thrust::device_ptr<float>]" matches the argument list
argument types are: (const thrust::device_reference<float>)
detected during:
instantiation of "thrust::detail::cons<HT, thrust::null_type>::cons(const thrust::detail::cons<HT2, thrust::null_type> &) [with HT=iter, HT2=thrust::device_reference<float>]"
(310): here
instantiation of "thrust::detail::cons<HT, TT>::cons(const thrust::detail::cons<HT2, TT2> &) [with HT=iter, TT=thrust::detail::cons<iter, thrust::null_type>, HT2=thrust::device_reference<float>, TT2=thrust::detail::cons<thrust::device_reference<float>, thrust::null_type>]"
C:\Program Files\NVIDIA GPU Computing Toolkit\CUDA\v7.5\bin/../include\thrust/tuple.h(361): here
instantiation of "thrust::tuple<T0, T1, T2, T3, T4, T5, T6, T7, T8, T9>::tuple(const thrust::detail::cons<U1, U2> &) [with T0=iter, T1=iter, T2=thrust::null_type, T3=thrust::null_type, T4=thrust::null_type, T5=thrust::null_type, T6=thrust::null_type, T7=thrust::null_type, T8=thrust::null_type, T9=thrust::null_type, U1=thrust::device_reference<float>, U2=thrust::detail::cons<thrust::device_reference<float>, thrust::null_type>]"
sandbox.cu(37): here

2 errors detected in the compilation of "C:/cygwin64/tmp/tmpxft_00001a90_00000000-10_sandbox.cpp1.ii".

最佳答案

解决了! tup应该是 thrust::tuple<float, float> , 不是 thrust::tuple<iter, iter> .完整解决方案:

#include <iostream>
#include <stdlib.h>
#include <thrust/device_vector.h>
#include <thrust/transform.h>
#include <thrust/tuple.h>
#include <thrust/transform_reduce.h>
#include <thrust/iterator/zip_iterator.h>

typedef thrust::device_vector<float> dvec;
typedef thrust::tuple<float, float> tup;

struct func
{
__device__ float operator()(tup t) //difsq
{
float f = thrust::get<0>(t) - thrust::get<1>(t);
return f*f;
}
};

int main()
{
dvec a(4, 3.f);
dvec b(4, 2.f);
auto begin = thrust::make_zip_iterator(thrust::make_tuple(a.begin(), b.begin()));
auto end = thrust::make_zip_iterator(thrust::make_tuple(a.end(), b.end()));
std::cout << thrust::transform_reduce(begin, end, func(), 0.0f, thrust::plus<float>()) << std::endl;
std::cout << "done" << std::endl;
return 0;
}

关于c++ - CUDA 推力 zip_iterator 元组 transform_reduce,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/36436432/

26 4 0
Copyright 2021 - 2024 cfsdn All Rights Reserved 蜀ICP备2022000587号
广告合作:1813099741@qq.com 6ren.com