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SSZAP

  SSZAP is a procedure and hence all parameters must always be specified on the command line. The syntax to invoke it is,

   > SSZAP <dataset> <ssds> <radius> <qmode>
SSZAP applies the quality operation specified by <qmode> to all pixels in <dataset> within a radius <radius> of the points in space defined by the positions of the sources in <ssds>. The value of <radius> should be specified in the spatial axis units of <dataset>. <qmode> should be any one of the quality operations supported by the CQUALITY application.

The first point to note is that <dataset> need not be the dataset which produced <ssds> -- in fact it can be any n-dimensional binned dataset as long as the pointing direction is the same as that which produced <ssds>. Consider the following example,

   > XSORT ... OUT=cube               ; Create data cube from instrument
                                      ; interface
   > PROJECT cube image 3             ; Collapse cube to image
   > PSS image 0.5 sources \          ; Source search the image using
                                      ; a noddy background value
   > SSZAP cube 0.02 sources IGNORE   ; Ignore data in cube within 0.02
                                      ; degrees of a source
   > INTERP cube intcube ...          ; Patch over data where sources were
   > PROJECT intcube better_bgnd 3    ; Create new bgnd model 
   > SSZAP cube 0.02 sources RESTORE  ; Reset quality in cube
   > PSS image better_bgnd ...        ; Improved source search



Asterix
Tue Oct 7 12:03:17 BST 1997