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

# Calculating travel times at given gridpoints
  N1=121  N2=369  D1=25  D2=25
  NUM='mtt-num.out'  MTT='mtt-tt.out'  # AMP='mtt-ap.out'
  mtt:
  echo.pl: "44649*1" ">mtt-ap.out"  # Unit amplitudes for weighting

# Minimizing the mean squared width of Gaussian beams
  gbopt: