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astAxOffset
-
Add an increment onto a supplied axis value
- Description:
This function returns an axis value formed by adding a signed axis
increment onto a supplied axis value.
For a simple Frame, this is a trivial operation returning the
sum of the two supplied values. But for other derived classes
of Frame (such as a SkyFrame) this is not the case.
- Synopsis:
double astAxOffset( AstFrame *this, int axis, double v1, double dist )
- Parameters:
-
this
-
Pointer to the Frame.
-
v1
-
The original axis value.
-
dist
-
The axis increment to add to the original axis value.
- Returned Value:
-
astAxOffset
-
The incremented axis value.
- Notes:
-
This function will return a "bad" result value (AST__BAD) if
any of the input vaues has this value.
-
A "bad" value will also be returned if this function is
invoked with the AST error status set, or if it should fail for
any reason.
Next: astBegin - Begin a new AST context
Up: AST Function Descriptions
Previous: astAxDistance - Find the distance between two axis values
AST A Library for Handling World Coordinate Systems in Astronomy
Starlink User Note 211
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