FALSEvalues for these flags.
TRUEvalue is supplied (the default), then it will be processed. Otherwise it will not be processed, so that the variance array (if present) may be considered on its own. The DATA and VARIANCE parameters should not both be set to
TRUEvalue is supplied for this parameter (the default), then the NDF’s bad-pixel flags will be permanently modified if necessary. If a
FALSEvalue is supplied, then no modifications will be made. This latter mode allows the routine to be used to check for the presence of bad pixels without changing the current state of an NDF’s bad-pixel flags. It also allows the routine to be used on NDFs for which write access is not available.
FALSEmakes it possible to check for bad pixels without permanently modifying the NDF.)
!) value is supplied for this parameter (the default), then the routine will check to see whether any bad pixels are present. This will only involve testing the value of each pixel if the bad-pixel flag value is initially
TRUE, in which case it will be reset to
FALSEif no bad pixels are found. If the bad-pixel flag is initially
FALSE, then it will remain unchanged.
If a logical (
FALSE) value is supplied for this parameter, then it indicates
the new bad-pixel flag value which is to be set. Setting a
TRUE value indicates to
later applications that there may be bad pixels present in the NDF, for which checks
must be made. Conversely, setting a
FALSE value indicates that there are definitely no
bad pixels present, in which case later applications need not check for them and should
interpret the pixel values in the NDF literally.
The VALUE parameter is not used (a null value is assumed) if the MODIFY parameter is
FALSE indicating that the NDF is not to be permanently modified.
TRUEvalue is supplied (the default), then it will be processed. Otherwise it will not be processed, so that the data array may be considered on its own. The DATA and VARIANCE parameters should not both be set to
FALSE. The action taken will be reported.
nodatainhibits processing of the data array, whose bad-pixel flag is left unchanged.
FALSE. Any pixel values which might previously have been regarded as bad will subsequently be interpreted literally as valid pixels.
TRUE. If any pixels have the special ‘bad’ value, then they will subsequently be regarded as invalid pixels. Note that if this is followed by a further command such as
"setbad hbeta", then an actual check will be made to see whether any pixels have this special value. The bad-pixel flags will be returned to
FALSEif they do not.
TRUE, it indicates that the associated NDF array may contain the special ‘bad’ value and that affected pixels are to be regarded as invalid. Subsequent applications will need to check for such pixels and, if found, take account of them.
Conversely, if a bad-pixel flag value is
FALSE, it indicates that there are
no bad pixels present. In this case, any special ‘bad’ values appearing in
the array are to be interpreted literally as valid pixel values.
However, if either of the NDF’s data or variance arrays do not contain any bad pixels themselves, a check will be made to see whether a QUALITY component is present. If it is (and its associated bad-bits mask is non-zero), then a warning message will be issued indicating that bad pixels may be introduced via this QUALITY component. If required, these bad pixels may be eliminated either by setting the bad-bits mask to zero or by erasing the QUALITY component.