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Section Arrays: Normalize¶

Adapted from: https://github.com/gjbex/Fortran-MOOC/tree/master/source_code/arrays

This program normalizes a randomly generated matrix in Fortran.¶

program normalize
  use, intrinsic :: iso_fortran_env, only : error_unit, DP => REAL64
  implicit none
  integer, parameter :: rows = 3, cols = 4
  real(kind=DP), dimension(rows, cols) :: matrix, spread_norm
  real(kind=DP), dimension(rows) :: norm

  call random_number(matrix)
  print '(A)', 'original:'
  call print_matrix(matrix)

  norm = sum(matrix, dim=2)
  print '(A, *(F12.7))', 'norm:', norm

  spread_norm = spread(norm, 2, size(matrix, 2))
  call print_matrix(spread_norm)

  matrix = matrix/spread_norm
  print '(A)', 'row-normalized::'
  call print_matrix(matrix)

  norm = sum(matrix, dim=2)
  print '(A, *(F12.7))', 'norm:', norm

contains

  subroutine print_matrix(matrix)
      implicit none
      real(kind=DP), dimension(:, :), intent(in) :: matrix
      integer :: row

      do row = 1, size(matrix, 1)
          print '(*(F12.7))', matrix(row, :)
      end do
  end subroutine print_matrix

end program normalize

The above program is compiled and run using Fortran Package Manager (fpm):

Build the Program using FPM (Fortran Package Manager)¶

import os
root_dir = os.getcwd()

code_dir = root_dir + "/" + "Fortran_Code/Section_Arrays_Normalize"

os.chdir(code_dir)

build_status = os.system("fpm build 2>/dev/null")

Run the Program using FPM (Fortran Package Manager)¶

exec_status = os.system("fpm run 2>/dev/null")

original:
   0.9819122   0.5656663   0.0519671   0.6593946
   0.4108865   0.3895287   0.9864829   0.4993061
   0.1143754   0.7222470   0.3168408   0.5699719
norm:   2.2589402   2.2862042   1.7234352
   2.2589402   2.2589402   2.2589402   2.2589402
   2.2862042   2.2862042   2.2862042   2.2862042
   1.7234352   1.7234352   1.7234352   1.7234352
row-normalized::
   0.4346783   0.2504122   0.0230051   0.2919044
   0.1797243   0.1703823   0.4314938   0.2183996
   0.0663648   0.4190741   0.1838426   0.3307185
norm:   1.0000000   1.0000000   1.0000000

exec_status = os.system("fpm run 2>/dev/null")

original:
   0.9050181   0.2726466   0.6853125   0.2627178
   0.5990356   0.6849099   0.2024486   0.6401817
   0.4520195   0.7993657   0.2001478   0.3209484
norm:   2.1256949   2.1265758   1.7724815
   2.1256949   2.1256949   2.1256949   2.1256949
   2.1265758   2.1265758   2.1265758   2.1265758
   1.7724815   1.7724815   1.7724815   1.7724815
row-normalized::
   0.4257516   0.1282623   0.3223946   0.1235915
   0.2816902   0.3220717   0.0951993   0.3010388
   0.2550207   0.4509868   0.1129195   0.1810729
norm:   1.0000000   1.0000000   1.0000000

exec_status = os.system("fpm run 2>/dev/null")

original:
   0.5397559   0.6360928   0.7468544   0.9909061
   0.2020675   0.2961180   0.5907776   0.1273281
   0.7599353   0.6659968   0.0851879   0.3199028
norm:   2.9136092   1.2162912   1.8310228
   2.9136092   2.9136092   2.9136092   2.9136092
   1.2162912   1.2162912   1.2162912   1.2162912
   1.8310228   1.8310228   1.8310228   1.8310228
row-normalized::
   0.1852534   0.2183178   0.2563331   0.3400957
   0.1661342   0.2434598   0.4857205   0.1046855
   0.4150332   0.3637294   0.0465247   0.1747126
norm:   1.0000000   1.0000000   1.0000000