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/*
* Distributed under the OSI-approved Apache License, Version 2.0. See
* accompanying file Copyright.txt for details.
*
* helloBPReaderHeatMap.cpp : Writes a regular heat map in a regular 2D mesh,
* values grow from 0 in increments of 1
*
* temperature[gNx, gNy]
* where: gNx = MPI_size_x * Nx and gNy = MPI_size_y * Ny
*
* 0 1 2 ... gNy-1
* gNy gNy+1 gNy+2 ... 2*gNy-1
* ...
* ...
* (gNx-1)*gNy ... gNx*gNy-1
*
*
* Created on: Nov 1, 2017
* Author: William F Godoy godoywf@ornl.gov
*/
#include <algorithm>
#include <ios> //std::ios_base::failure
#include <iostream> //std::cout
#include <mpi.h>
#include <stdexcept> //std::invalid_argument std::exception
#include <vector>
#include <adios2.h>
int main(int argc, char *argv[])
{
MPI_Init(&argc, &argv);
int rank, size;
MPI_Comm_rank(MPI_COMM_WORLD, &rank);
MPI_Comm_size(MPI_COMM_WORLD, &size);
/** Application variable dimensions */
constexpr std::size_t Nx = 10;
constexpr std::size_t Ny = 10;
const adios2::Dims count{Nx, Ny};
const adios2::Dims start{rank * Nx, rank * Ny};
const adios2::Dims shape{size * Nx, size * Ny};
// populate local temperature values
std::vector<unsigned int> temperatures(Nx * Ny);
for (unsigned int i = 0; i < Nx; ++i)
{
const unsigned int iGlobal = start[0] + i;
for (unsigned int j = 0; j < Ny; ++j)
{
const unsigned int jGlobal = start[1] + j;
const unsigned int value = iGlobal * shape[1] + jGlobal;
temperatures[i * Ny + j] = value;
}
}
try
{
/** ADIOS class factory of IO class objects, Debug is ON by default */
adios2::ADIOS adios(MPI_COMM_WORLD);
// ************************** WRITE
/*** IO class object: settings and factory of Settings: Variables,
* Parameters, Transports, and Execution: Engines */
adios2::IO &putHeatMap = adios.DeclareIO("HeatMapWriter");
adios2::Variable<unsigned int> &outTemperature =
putHeatMap.DefineVariable<unsigned int>(
"temperature", shape, start, count, adios2::ConstantDims);
/** Will create HeatMap.bp */
adios2::Engine &bpWriter =
putHeatMap.Open("HeatMap.bp", adios2::Mode::Write);
bpWriter.PutSync(outTemperature, temperatures.data());
bpWriter.Close();
// ************************** READ
if (rank == 0)
{
adios2::IO &getHeatMap = adios.DeclareIO("HeatMapReader");
adios2::Engine &bpReader =
getHeatMap.Open("HeatMap.bp", adios2::Mode::Read);
// this just discovers in the metadata file that the variable exists
adios2::Variable<unsigned int> *inTemperature =
getHeatMap.InquireVariable<unsigned int>("temperature");
// inTemperature->SetSelection({{,0})
// now read the variable
if (inTemperature != nullptr)
{
std::vector<unsigned int> inTemperatures(Nx * Ny);
bpReader.GetSync(*inTemperature, inTemperatures.data());
for (auto i = 0; i < inTemperatures.size(); ++i)
{
std::cout << inTemperatures[i] << " ";
if (i % Nx == 0 && i > 0)
{
std::cout << "\n";
}
}
std::cout << "\n";
}
bpReader.Close();
}
}
catch (std::invalid_argument &e)
{
std::cout << "Invalid argument exception, STOPPING PROGRAM from rank "
<< rank << "\n";
std::cout << e.what() << "\n";
}
catch (std::ios_base::failure &e)
{
std::cout << "IO System base failure exception, STOPPING PROGRAM "
"from rank "
<< rank << "\n";
std::cout << e.what() << "\n";
}
catch (std::exception &e)
{
std::cout << "Exception, STOPPING PROGRAM from rank " << rank << "\n";
std::cout << e.what() << "\n";
}
MPI_Finalize();
return 0;
}