m_random

Description

Derived type to hold a random number generator, which does not interfere with the global RANDOM_NUMBER() routine of fortran.

Using t_random can be useful when coupling software which depend on specifically seeded random number generator for internal use, and should not clash with another.

Compile

Straightforward compile command:

gfortran -c m_random.f90

Caller program

Link the caller program with m_random.o object by specifying the include path -I to src. See also the test/compile.sh script.

Example program:

program main

  use m_random, only: t_random
  implicit none

  type( t_random ), pointer :: rd1, rd2
  real :: z
  real :: zv(6)

  ! initialize with specific seed
  rd1 => t_random( 1234 )

  ! initialize another type
  rd2 => t_random( 5678 )

  ! generate numbers
  call rd1% random_number( z )

  ! or vectors
  call rd2% random_number( zv )

  ! re-seed to another value
  call rd1% reseed( 6543 )

  ! finalize
  deallocate( rd1 )
  deallocate( rd2 )
end program main