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Norm(axis) - Specifies the plane upon which a Plot3D draws text and markers

Description:
This attribute controls the appearance of text and markers drawn by a Plot3D. It specifies the orientation of the plane upon which text and markers will be drawn by all subsequent invocations of the astText and astMark functions.

When setting or getting the Norm attribute, the attribute name must be qualified by an axis index in the range 1 to 3. The 3 elements of the Norm attribute are together interpreted as a vector in 3D graphics coordinates that is normal to the plane upon which text and marks should be drawn. When testing or clearing the attribute, the axis index is optional. If no index is supplied, then clearing the Norm attribute will clear all three elements, and testing the Norm attribute will return a non-zero value if any of the three elements are set.

The default value is 1.0 for each of the 3 elements. The length of the vector is insignificant, but an error will be reported when attempting to draw text or markers if the vector has zero length.

Type:
Floating point.
Class Applicability:
Plot
All Plot3Ds have this attribute.


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AST A Library for Handling World Coordinate Systems in Astronomy
Starlink User Note 211
R.F. Warren-Smith & D.S. Berry
7th December 2012
E-mail:starlink@jiscmail.ac.uk

Copyright (C) 2012 Science \& Technology Facilities Council