The routine applies pixel-index shifts to an NDF. An integer shift is applied to each dimension so that its pixel-index bounds, and the indices of each pixel, change by the amount of shift applied to the corresponding dimension. The NDF’s pixels retain their values and none are lost.

CALL NDF_SHIFT( NSHIFT, SHIFT, INDF, STATUS )

NSHIFT = INTEGER (Given)

SHIFT( NSHIFT ) = INTEGER (Given)

INDF = INTEGER (Given)

STATUS = INTEGER (Given and Returned)

• Pixel-index shifts applied to a base NDF will affect the appearance of that NDF as seen by all base-NDF identifiers associated with it. However, NDF sections derived from that base NDF will remain unchanged (as regards both pixel-indices and array values).

• Pixel-index shifts applied to an NDF section only affect that section itself, and have no effect on other NDF identifiers.

• Pixel-index shifts cannot be applied to a base NDF while any of its components (or any of its axis arrays) is mapped for access, even through another identifier.

• Pixel-index shifts cannot be applied to an NDF section while any of its components (or any of its axis arrays) is mapped for access through the identifier supplied to this routine.