Changes Introduced in V5.7-1

The following describes the most significant changes which occurred in the AST library between versions V5.7-0 and V5.7-1:

1. - All classes of Channel can now read to and write from specified text files, without the need to provide source and sink functions when the Channel is created. The files to use are specified by the new attributes SourceFile and SinkFile.

2. - The FitsChan class now ignores trailing spaces in character-valued WCS keywords when reading a FrameSet from a FITS header.

3. - If the FitsChan astRead method reads a FITS header that uses the -SIP (Spitzer) distortion code within the CTYPE values, but which does not provide an inverse polynomial correction, the FitsChan class will now use the PolyTran method of the PolyMap class to create an estimate of the inverse polynomial correction.