#### Description:

This read-only attribute contains a textual representation of the physical units used to represent unformatted (i.e. floating point) values on a particular axis of a Frame, typically handled internally within application code. In most cases, the value of the InternalUnit attribute will be the same as Unit attribute (i.e. formatted and unformatted axis values will normally use the same system of units). The main exception to this is the SkyFrame class, which represents unformatted axis values in radians, regardless of the current setting of the Unit attribute.

Type:

  String, read-only.

#### Applicability

##### Frame

All Frames have this attribute.

#### Notes:

- When specifying this attribute by name, it should be subscripted with the number of the Frame axis to which it applies.

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