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// simple example that shows how to work with zfp's compressed-array classes
#include <iostream>
#include <vector>
#include "zfp/array2.hpp"
int main()
{
// array dimensions (can be arbitrary) and zfp memory footprint
const size_t nx = 12;
const size_t ny = 8;
const double bits_per_value = 4.0;
// declare 2D arrays using STL and zfp
std::vector<double> vec(nx * ny);
zfp::array2<double> arr(nx, ny, bits_per_value);
// initialize arrays to linear ramp
for (size_t y = 0; y < ny; y++)
for (size_t x = 0; x < nx; x++)
arr(x, y) = vec[x + nx * y] = x + nx * y;
// alternative initialization of entire array, arr:
// arr.set(&vec[0]);
// optional: force compression of cached data
arr.flush_cache();
// print values
for (size_t y = 0; y < ny; y++)
for (size_t x = 0; x < nx; x++)
std::cout << vec[x + nx * y] << " " << arr(x, y) << std::endl;
// alternative using printf(); note the necessary cast:
// printf("%g %g\n", vec[x + nx * y], (double)arr(x, y));
// print storage size of payload data
std::cout << "vec bytes = " << vec.capacity() * sizeof(vec[0]) << std::endl;
std::cout << "zfp bytes = " << arr.size_bytes(ZFP_DATA_PAYLOAD) << std::endl;
return 0;
}
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