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- 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:
-
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.
Next: AST Attribute Descriptions
Up: AST Routine Descriptions
Previous: AST_WRITE - Write an Object to a Channel
AST A Library for Handling World Coordinate Systems in Astronomy
Starlink User Note 210
R.F. Warren-Smith & D.S. Berry
30th April 2003
E-mail:ussc@star.rl.ac.uk
Copyright (C) 2003 Central Laboratory of the Research Councils