With this subroutine the user can define an amplitude. It is triggered bythe parameter USER on the *AMPLITUDE card. The header and variable description is as follows:
subroutine uamplitude(time,name,amplitude)
!
! user subroutine uamplitude: user defined amplitude definition
!
! INPUT:
!
! name amplitude name
! time time at which the amplitude is to be
! evaluated
!
! OUTPUT:
!
! amplitude value of the amplitude at time
!