Syntax: combine (poly. wavelength calib. FITS file 1) [FITS file 2] [FITS file 3] ... of=(output filename) [wr=bluewave:redwave] [-loglin] (disp=d) [zero=w] [-lgi] [-patch] Combines 2-D spectrum images into a 1-D spectrum. The error file filenames should be in one of several acceptable formats: Flux-*,Err-* ; F-*,E-* ; FF-*,FE-* ; *.fits,*e.fits . Options: -loglin : use a log-linear relation. In this case, disp= is equal to the velocity width of each bin in km/s . disp=d : align such that the Angstroms per pixel is "d". (Default is the average pixel width for each row.) zero=w : specifies that the spectra should be aligned such the wavelength "w" would be at the center of a bin. (Default value is 3000.) -lgi : Do lagrangian (area polynomial) interpolation (not recommended.) -patch : Interpolate over zero valued (masked) points.