# A CLASSic Session

       1    device image white
       2    set angle seconds
       3    set coordinates equatorial
       4    file in raw.30m
       5    set line 13co(1-0)
       6    set source ic348
       7    set telescope iram-30m-b30
       8    set observed 15-aug-1984
       9    find /offset 0  25
      10    set weight time
      11    average
      12    set unit v f
      13    set mode x -1 14
      14    set mode y -0.5 7.5
      15    set plot histogram
      16    plot
      17    hardcopy /print
      18    hardcopy spectrum.ps  /dev ps fast
      19    hardcopy spectrum.eps /dev eps color
      20    set window 3 6 8 10
      21    base 4 /plot
      22    plot
      23    lines 0
      24    gauss
      25    fit
      26    residual
      27    plot
      28    sic delete reduced.30m
      29    file out reduced.30m new
      30    swap
      31    write
      32    save ic348
      33    exit

1 | Define the output device.
2-3 | Select the coordinate system and angle unit.
4 | Open the input file.
5-9 | Build the index according to various criteria.
10-11 | Averaged all spectra with weights .
12-16 | Plot the averaged spectrum in a given velocity interval, with velocity for the lower axis and rest frequency for the upper axis.
17-20 | Make hardcopies (directly to the printer, in a ps or eps file).
21-23 | Subtract a polynomial baseline. Plot the fitted baseline. Plot the baseline subtracted spectrum. The baseline does not take into account channels corresponding to in the two specified windows, in current units (here velocity).
24-26 | Perform single Gaussian fitting and plot the result.
27-28 | Compute the residuals and plot them.
29-30 | Open a new output file.
31 | Recover the baseline subtracted spectrum.
32 | Write it.
33 | Write the input commands in file ic348.class.