example_no_array.cpp File Reference

#include <array>
#include <vector>
#include <algorithm>
#include <cassert>
#include <iostream>

Go to the source code of this file.

Functions
void	gather_no_array (const float *in_data, const std::array< size_t, 3 > &dims, float *out_data, const std::array< size_t, 3 > &out_dims, const int *indices, const std::array< size_t, 3 > &indices_dims)
int	main ()

Function Documentation

gather_no_array()

void gather_no_array	(	const float *	in_data,
		const std::array< size_t, 3 > &	dims,
		float *	out_data,
		const std::array< size_t, 3 > &	out_dims,
		const int *	indices,
		const std::array< size_t, 3 > &	indices_dims
	)

Definition at line 23 of file example_no_array.cpp.

{
  assert(indices_dims[1] == dims.size());
 
  for (int i = 0; i < indices_dims[0]; ++i)
  {
    for (int j = 0; j < indices_dims[1]; ++j)
    {
      const int *index_ptr = indices + i * indices_dims[2] * indices_dims[1] + j * indices_dims[2];
 
      size_t in_offset = index_ptr[0] * dims[2] * dims[1] + index_ptr[1] * dims[2];
 
      const float *in_ptr = in_data + in_offset;
 
      size_t out_offset = i * out_dims[2] * out_dims[1] + j * out_dims[2];
 
      float *out_ptr = out_data + out_offset;
 
      for (int k = 0; k < dims[2]; ++k)
      {
        out_ptr[k] = in_ptr[k];
      }
    }
  }
}

Referenced by main().

main()

int main

(

void

)

Definition at line 51 of file example_no_array.cpp.

{
  std::array<size_t, 3> in_dims{3, 3, 4};
  std::vector<float> input(3 * 3 * 4);
  for (size_t i = 0; i < 3 * 3 * 4; ++i)
    input[i] = i;
 
  std::array<size_t, 3> indices_shape{1, 3, 2};
  std::vector<int> indices(1 * 3 * 2);
 
  indices[0] = 0;
  indices[1] = 0;
  indices[2] = 1;
  indices[3] = 1;
  indices[4] = 2;
  indices[5] = 2;
 
  std::array<size_t, 3> output_dims{1, 3, 4};
  std::vector<float> output(1 * 3 * 4);
 
  gather_no_array(input.data(), in_dims, output.data(), output_dims, indices.data(), indices_shape);
 
  for (size_t i = 0; i < output_dims[0]; ++i)
  {
    for (size_t j = 0; j < output_dims[1]; ++j)
    {
      auto out_ptr = output.data() + i * output_dims[1] * output_dims[2] + j * output_dims[2];
      for (size_t k = 0; k < output_dims[2]; ++k)
      {
        std::cout << out_ptr[k] << ", ";
      }
      std::cout << std::endl;
    }
  }
}

References gather_no_array().