##
##  Create track irregularities via a function
##  ==========================================
##
##  Following text replaces the command 
##  "func intpl_r lat_trac" in your input data file.
##
   func const     ampl=   2.  # Amplitude=  2.
   func const     frekvd= 5.  # Wave length 5.
#
   func operp     dist=      Vo * time
   func operp     tracsig= ampl * sin( 6.28318531 * frekvd * dist )
#
   func fifo_mem2 lat_trac   tracsig 100  1  dist