Maximum number of Frame axes to match


This attribute controls how a Frame behaves when it is used (by AST_FINDFRAME) as a template to match another (target) Frame. It specifies the maximum number of axes that the target Frame may have in order to match the template.

Normally, this value will equal the number of Frame axes, so that a template Frame will only match another Frame with the same number of axes as itself. By setting a different value, however, the matching process may be used to identify Frames with specified numbers of axes.



The default MaxAxes value for a Frame is equal to the number of Frame axes (Naxes attribute).
The MaxAxes attribute of a CmpFrame defaults to a large number (1000000) which is much larger than any likely number of axes in a Frame. Combined with the MinAxes default of zero (for a CmpFrame), this means that the default behaviour for a CmpFrame is to match any target Frame that consists of a subset of the axes in the template CmpFrame. To change this so that a CmpFrame will only match Frames that have the same number of axes, you should set the CmpFrame MaxAxes and MinAxes attributes to the number of axes in the CmpFrame.
The MaxAxes attribute of a FrameSet is the same as that of its current Frame (as specified by the Current attribute).