## Changes Introduced in V5.3-2

The following describes the most significant changes which occurred in the AST library between versions V5.3-1 and V5.3-2:

1. A bug has been fixed in the FitsChanFitsChan class that could cause wavelength axes to be assigned the units “m/s” when reading WCS information from a FITS header.

2. The astSetastSet function now allows literal commas to be included in string attribute values. String attribute values that include a literal comma should be enclosed in quotation marks.

3. A bug in FitsChan has been fixed that caused “-SIN” projection codes within FITS-WCS headers to be mis-interpreted, resulting in no FrameSetFrameSet being read by astReadastRead.

4. The KeyMapKeyMap class has a new attribute called “SortBySortBy”. It controls the order in which keys are returned by the astMapKeyastMapKey function. Keys can be sorted alphabetically or by age, or left unsorted.

5. Access to KeyMaps holding thousands of entries is now significantly faster.

6. KeyMaps can now hold word (i.e. short integer) values.