#### Description:

This attribute specifies which type of FITS-WCS projection will be performed by a WcsMap. The value is specified when a WcsMap is first created using astWcsMap and cannot subsequently be changed.

The values used are represented by macros with names of the form `"` AST__XXX`"` , where `"` XXX`"` is the (upper case) 3-character code used by the FITS-WCS `"` CTYPEi`"` keyword to identify the projection. For example, possible values are AST__TAN (for the tangent plane or gnomonic projection) and AST__AIT (for the Hammer-Aitoff projection). AST__TPN is an exception in that it is not part of the FITS-WCS standard (it represents a TAN projection with polynomial correction terms as defined in an early draft of the FITS-WCS paper).

Type:

  Integer, read-only.

#### Applicability

##### WcsMap

All WcsMaps have this attribute.

#### Notes:

- For a list of available projections, see the FITS-WCS paper.

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