ex.02.array-csr/main.cpp

Example illustrating access to elements in a dash::Array by global index and the CSR pattern.

#include <iostream>
#include <string>
#include <vector>

#include <unistd.h>
#include <cstddef>

#ifndef DASH_ENABLE_LOGGING
#define DASH_ENABLE_LOGGING
#endif

#include <libdash.h>

using std::cout;
using std::endl;

int main(int argc, char* argv[])
{
  typedef dash::CSRPattern<1>           pattern_t;
  typedef size_t                        value_t;
  typedef int                           index_t;
  typedef typename pattern_t::size_type extent_t;

  dash::init(&argc, &argv);

  char   buf[100];
  pid_t  pid            = getpid();
  auto   myid           = dash::myid();
  size_t num_units      = dash::size();
  size_t max_local_size = 100;

  gethostname(buf, 100);

  DASH_LOG_DEBUG("Host:",  buf,
                 "PID:",   pid,
                 "Units:", num_units);

  std::vector<extent_t> local_sizes;
  for (size_t unit_idx = 0; unit_idx < num_units; ++unit_idx) {
    local_sizes.push_back(((unit_idx + 11) * 23) % max_local_size);
  }
  pattern_t pattern(local_sizes);

  if (myid == 0) {
    DASH_LOG_DEBUG("Pattern size:     ", pattern.size());
    DASH_LOG_DEBUG("Block sizes:      ", local_sizes);
  }
  DASH_LOG_DEBUG("Local size:       ", pattern.local_size());

  dash::Array<value_t, index_t, pattern_t> array(pattern);

  if (myid == 0) {
    DASH_LOG_DEBUG("Array size:      ", array.size());
  }
  DASH_LOG_DEBUG("Array local size:   ", array.lsize());

  dash::finalize();

  return 0;
}