# Plotting widths of Gaussian beams for a given receiver position
# ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
# Grid for interpolation within ray cells
  N1=60  N2=184  D1=50  D2=50  O1=25  O2=25

# Ray tracing
# ~~~~~~~~~~~
  MODEL='mar-mod.dat'  # Model
  SRC='mar-src.out'    # File with the coordinates of the initial point
  REC=' '              # No receivers in this example
  DCRT='mar-crt.dat'   # Numerical parameters for complete ray tracing
  CODE='codep.dat'     # Ray codes (direct P wave)
  INIPAR=2             # Geographic-like spherical ray parameters
  RPAR='mar-crt.dat'   # Ray-parameter domain and control
  WRIT='writall.dat'   # Names and extent of output files with rays
  CRTLOG='mar-log.out' # Output log file of ray tracing
  crt:                 # Running program crt.for with the above data

# Interpolation between rays
# ~~~~~~~~~~~~~~~~~~~~~~~~~~
  NTIME=26   OTIME=0.1    DTIME=0.1
  NPAR1=181  OPAR1=-1.57  DPAR1=0.017348
  FGBR22='fgbr22.out'  FGBY22='fgby22.out'  # Initial shape of GBs
  GBE11=0  GBE21=0  GBE31=1  # Reference plane for the shape of GBs
  MTT=' '  GBW2='mar-gbw.out'  # No travel times, file with GB width
  NUM='mar-num.out'
  mtt:
# Calculating maximum width of Gaussian beams over arrivals
  MGRD='mar-gbw.out' GRD='mar-gbw.tmp'
  mgrd:
  N4NEW=1  GNORM=999  # data for 'grdnorm.for' to compute maximum
  GRDNEW='mar-gbm.out'
  grdnorm:
  N4=1
# 'mar-num.out'... numbers of arrivals
# 'mar-gbm.out'... maximum widths of Gaussian beams over arrivals

# Plotting widths of Gaussian beams for given initial conditions
# ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
# Removing large GB widths for plotting
  echo.pl: "@2=MIN(@1,15000)" ">grdcal.tmp"
  CAL='grdcal.tmp' GRD1='mar-gbm.out' GRD2='mar-gb.tmp'
  grdcal:
# Plotting maximum widths of Gaussian beams
  HSIZE=5.4  VOFFSET=2.22  ROTATE=-90
  CREF=0.166667  VREF=0  VCIRC=18000  VMIN=
# 0 yellow, 3000 green, 6000 cyan, 9000 blue, 12000 magenta, 15000+ red
  GRD='mar-gb.tmp'  PS='mar-gb.ps'
  grdps:
# 'mar-gb.ps'... plot of maximum widths of Gaussian beams over arrivals