This function creates a new NormMap and optionally initialises its attributes.

A NormMap is a Mapping which normalises coordinate values using the AST_NORM routine of the supplied Frame. The number of inputs and outputs of a NormMap are both equal to the number of axes in the supplied Frame.

The forward and inverse transformation of a NormMap are both defined but are identical (that is, they do not form a real inverse pair in that the inverse transformation does not undo the normalisation, instead it reapplies it). However, the AST_SIMPLIFY function will replace neighbouring pairs of forward and inverse NormMaps by a single UnitMap (so long as the Frames encapsulated by the two NormMaps are equal - i.e. have the same class and the same attribute values). This means, for instance, that if a CmpMap contains a NormMap, the CmpMap will still cancel with its own inverse.

RESULT = AST_NORMMAP( FRAME, OPTIONS, STATUS )

FRAME = INTEGER (Given)

OPTIONS = CHARACTER $\ast$ ( $\ast$ ) (Given)

STATUS = INTEGER (Given and Returned)

AST_NORMMAP = INTEGER

• A null Object pointer (AST__NULL) will be returned if this function is invoked with STATUS set to an error value, or if it should fail for any reason.

The protected interface to this function includes an extra parameter at the end of the parameter list descirbed above. This parameter is a pointer to the integer inherited status variable: " int $\ast$status" .