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Amplitude

User defined amplitudes

This subroutine is used for user-defined amplitude values, characterized by the parameter *Amplitude, type=user command in the input file. The header and variable description are given in the following. Notice that numgeo searches for the file user_amplitude.so in the current working directory.

Linux

subroutine user_amplitude(time,nprops,props,value) bind(c,name='user_amplitude')
use, intrinsic :: iso_c_binding
  implicit none
  real(c_double)                    , intent(in)    :: time  
  integer(c_int)                    , intent(in)    :: nprops
  real(c_double), dimension(nprops) , intent(in)    :: props 
  real(c_double), dimension(3)      , intent(inout) :: value    

  ... user coding

end subroutine user_amplitude

Windows

subroutine user_amplitude(time,nprops,props,value) 
  implicit none
  !DEC$ ATTRIBUTES DLLEXPORT, STDCALL, REFERENCE :: user_amplitude
  real(8)                    , intent(in)    :: time                !! current step time 
  integer                    , intent(in)    :: nprops              !! number of user specified properties
  real(8), dimension(nprops) , intent(in)    :: props               !! properties of this amplitude
  real(8), dimension(3)      , intent(inout) :: value               !! value of this amplitude     

... user coding

end subroutine user_amplitude

  • time: Step time

  • nprops: Number of properties defined in the input file

  • props(:): Properties defined in the input file

  • value(:): Total value of the amplitude at the given time. If the analysis procedure requires that the time derivatives of prescribed variables be defined (for example, in a dynamic analysis the velocity and acceleration, as well as the value of the variable, are needed), must be given in bc_value(2) and in bc_value(3).