#### Description:

This attribute is a boolean value which is used when a FrameSet is read from a FitsChan with a foreign FITS encoding (e.g. FITS-WCS) using astRead. If it has a non-zero value then the returned FrameSet will include Frames representing `"` intermediate world coordinates`"` (IWC). These Frames will have Domain name `"` IWC`"` for primary axis descriptions, and `"` IWCa`"` for secondary axis descriptions, where `"` a`"` is replaced by the single alternate axis description character, as used in the FITS-WCS header. The default value for `"` Iwc`"` is zero.

FITS-WCS paper 1 defines IWC as a Cartesian coordinate system with one axis for each WCS axis, and is the coordinate system produced by the rotation matrix (represented by FITS keyword PCi_j, CDi_j, etc). For instance, for a 2-D FITS-WCS header describing projected celestial longitude and latitude, the intermediate world coordinates represent offsets in degrees from the reference point within the plane of projection.

Type:

  Integer (boolean).

#### Applicability

##### FitsChan

All FitsChans have this attribute.
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