KPG1_PIXSC

Determines formatted pixel scales at a given grid position

Description:

This routine determines the scales of the WCS axes in the current Frame of the supplied FrameSet, and formated them into a string. For a specified WCS axis, the returned scale is the WCS axis increment produced by moving a distance of one grid pixel away from the supplied " AT" position, along the WCS axis.

Invocation

CALL KPG1_PIXSC( IWCS, AT, PIXSC, VALUE, UNIT, STATUS )

Arguments

IWCS = INTEGER (Given)
The FrameSet.
AT( ∗ ) = DOUBLE PRECISION (Given)
The position in GRID co-ordinates at which the pixel scales are to be determined. Note, the pixel scales may vary across the data array if the WCS Mappings are non-linear. The array should have one element for each GRID axis.
PIXSC( ∗ ) = DOUBLE PRECISION (Returned)
The returned pixel scales. Note, the pixel scale for both celestial longitude and latitude axes are returned as an arc-distance in radians. The array should have one element for each WCS axis.
VALUE( ∗ ) = CHARACTER( ∗ ) (Returned)
The formatted pixel scales. Celestial axes are formatted as arc-seconds using a " G15.6" format. Time values are also formatted using G15.6 (the Format attribute in the current WCS Frame is ignored, since it may produce a calendar date), in what ever units are indicated in the current Frame. Other types of axes (including spectral axes) are formatted using the axis Format attribute in the current WCS Frame. The array should have one element for each WCS axis. Each element of the array should be at least 15 characters long. The returned text is left justified.
UNIT( ∗ ) = CHARACTER( ∗ ) (Returned)
Units strings that describe the values returned in VALUES. The array should have one element for each WCS axis.
STATUS = INTEGER (Given and Returned)
The global status.