Symbol(axis)

Axis symbol

Description:

This attribute specifies a short-form symbol to be used to represent coordinate values for a particular axis of a Frame. This might be used (e.g.) in algebraic expressions where a full description of the axis would be inappropriate. Examples include " RA" and " Dec" (for Right Ascension and Declination).

If a Symbol value has not been set for a Frame axis, then a suitable default is supplied.

Type:
String.

Applicability

Frame
The default Symbol value supplied by the Frame class is the string " <Domain > <n >" , where <n > is 1, 2, etc. for successive axes, and <Domain > is the value of the Frame’ s Domain attribute (truncated if necessary so that the final string does not exceed 15 characters). If no Domain value has been set, " x" is used as the <Domain > value in constructing this default string.
SkyFrame
The SkyFrame class re-defines the default Symbol value (e.g. to " RA" or " Dec" ) as appropriate for the particular celestial coordinate system being represented.
TimeFrame
The TimeFrame class re-defines the default Symbol value as appropriate for the particular time system being represented.
FrameSet
The Symbol attribute of a FrameSet axis is the same as that of its current Frame (as specified by the Current attribute).

Notes:

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