smear

 SMEAR N1 N2 N3 WIDTH METHOD -- Smears spectra to simulate a uniform
                               translation across detector caused by
                               binary motion for example

 Parameters:
           
     N1   -- First spectrum to be smeared
     N2   -- Last spectrum to be smeared
     N3   -- First output spectrum
     WIDTH-- Total width of rectangular smear profile
     METHOD- F = Fast crude method, which is only accurate if
                 the broadening covers many pixels, otherwise it
                 tends to underbroaden. It is only worth using
                 on spectra which are not on a velocity scale since
                 the time saving is otherwise small.

             S = Slow accurate method which requires convolving the
                 broadening with the interpolating function for which
                 a truncated SIN(X)/X type interpolation is used.
                 BE WARNED: this can be VERY VERY slow see next.

     If the scale is uniform in velocity, then the routine need only 
     compute the blurring array once and the computation should not be 
     much affected by the METHOD used. Otherwise the blurring array is 
     recomputed for EVERY pixel assuming that the scale is locally a 
     velocity scale according to the disperion at the pixel of interest. 

This command belongs to the classes: arithematic and manipulation .