Reading a Distributed Matrix

• Problem: read a matrix with column-block distribution
  usual distribution of matrix:

  • 
  matrix gets automatically distributed when read in with the following filetype:

  • Etype: MPI_INT,
  • Filetype: as described above
• Remarks to the program (array1d.c):
  datatype for distributed matrix as in example oneside
  easy creation of the MPI datatype for fileview with the new function MPI_Type_create_subarray
  input file IN2 contains 100x100 integers a(i,j) with a(i,j) = 1000*i+j
  created with the program create_files.c
  check the result in all tasks