[SIC\]MODIFY VarName|GDFName [/FREQUENCY Linename RestFreq] [/VELOC- ITY Velocity] [/SPECUNIT FREQUENCY|VELOCITY] Modify consistently the spectroscopic axis of a lmv cube or a Sic struc- ture of type IMAGE, HEADER, or UVTABLE. The spectroscopic axis can be changed to the alternate unit with the op- tion /SPECUNIT. By default, the unit is unchanged.