FITS-WCS projection parameters
Attributes ProjP(0) to ProjP(9) correspond to attributes PV<axlat>_0 to PV<axlat>_9, where <axlat> is replaced by the index of the latitude axis (given by attribute WcsAxis(2)). See PV for further details.
Note, the value of this attribute may changed only if the WcsMap has no more than one reference. That is, an error is reported if the WcsMap has been cloned, either by including it within another object such as a CmpMap or FrameSet or by calling the AST_CLONE function.