Example

In the following example, MyScalar is a grid scalar which is declared in the interface.ccl as CCTK_REAL.

      subroutine InitialData(CCTK_ARGUMENTS)

      DECLARE_CCTK_ARGUMENTS

      CCTK_REAL local_var

      local_var = 1.0/3.0
      MyScalar = local_var

      return
      end

Declaring local_var to have a non-Cactus data type, e.g. REAL*4, or using one of the other Cactus real data types described in Section B10.8, could give problems for different architectures or configurations.