AST_ZOOMMAP

Create a ZoomMap

Description:

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

A ZoomMap is a Mapping which " zooms" a set of points about the origin by multiplying all coordinate values by the same scale factor (the inverse transformation is performed by dividing by this scale factor).

Invocation

RESULT = AST_ZOOMMAP( NCOORD, ZOOM, OPTIONS, STATUS )

Arguments

NCOORD = INTEGER (Given)
The number of coordinate values for each point to be transformed (i.e. the number of dimensions of the space in which the points will reside). The same number is applicable to both input and output points.
ZOOM = DOUBLE PRECISION (Given)
Initial scale factor by which coordinate values should be multiplied (by the forward transformation) or divided (by the inverse transformation). This factor may subsequently be changed via the ZoomMap s Zoom attribute. It may be positive or negative, but should not be zero.
OPTIONS = CHARACTER ( ) (Given)
A character string containing an optional comma-separated list of attribute assignments to be used for initialising the new ZoomMap. The syntax used is identical to that for the AST_SET routine.
STATUS = INTEGER (Given and Returned)
The global status.

Returned Value

AST_ZOOMMAP = INTEGER
A pointer to the new ZoomMap.

Notes:

Status Handling

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 status" .