The spectrum is written to stdout. as ASCII numbers with the index number (of either rows or columns) in the first column and the spectrum value in the second.
If the norm option is specified the resulting spectrum is divided by the number of rows in the spectrum.
The default is that sp specifies row numbers along which to take the spectrum. If cols is specified, then the spectrum is formed from the columns named in sp. The spectrum can be constrained to lie with a box specified on the command line. This option does not influence the row/cols selected by the sp or bk options but only the perpendicular axis.
mash lyr sp=20,30 bk=5,10 bk=40,45 norm
Generates a spectrum from file `lyr.fts' using rows 20-29 inclusively for the spectrum and subtracting the sum of rows 5-9 and 40-44 as a background. Since the norm flag was specified the resulting spectrum is divided by 5.