The evolution of spectra against time can be displayed as a contour map by
BCS_CONT, or as a greyscale image using DISP_BDA and GS. Note: The time
axis of BCS_CONT is uniform, but those of DISP_BDA and GS are not.
Example calls of these routines are:
IDL> bcs_cont,index,data [,chan=n, range=[n1,n2], etc.]
IDL> disp_bda,index,data
IDL> .run gs