This parameter specifies the mask that defines the area over which the normalised map change should be calculated when determining the mean or maximum map change at the end of each iteration. See parameter "maptol" . The supplied value can be " AST" , " FLT" , " COM" , " PCA" or " $<$undef$>$" . If the specifies mask is not defined, or if " $<$undef$>$" is supplied, then the map change is determined over the entire map. [AST]

MAKEMAP, CALCQU