Starlink-pyast

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- A new function call astCreatedAt is now available that returns the function
name, file path and line number at which an AST object was first created.

- The number of digits used to format floating point values has been
increased in order to avoid loss of precision when converting from binary
to string and back to binary. This could cause very small changes in numerical
values returned by AST functions.

- If a FrameSet is supplied as the "Map" argument to astAddFrame, it now
extracts and stores the base->current Mapping from the supplied FrameSet.
Previously, the entire FrameSet was stored as the Mapping.

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- A new class of Mapping called ChebyMap has been added. This is a
Mapping that implements Chebyshev polynomial transformations.

- If the function that delivers error messages to the user (astPutErr) is
re-implemented, the new version can now be registered at run-time using
the new astSetPutErr function. Previously, the new version needed to be
linked into the application at build time.

- A bug has been fixed in the PolyMap class that caused incorrect values
to be returned for the TranForward and TranInverse attributes if the PolyMap
has been inverted.

- The KeyMap class has a new method called astMapGetC (AST_MAPGETC) which
returns a named entry as a single string. If the entry is a vector the
returned string is a comma-separated list of its elements, enclosed in
parentheses.

- The Frame class now has a new attribute caled DTAI, which can be used
to specify the number of leap seconds at the moment represented by the
Frame's Epoch attribute. By default, the internal look-up table of leap
seconds contained within AST is used. The DTAI attribute allows old
versions of AST, which may not include the most recent leap seconds, to
be used with new data.

- The TimeMap class has been changed so that some conversions now require
a "Dtai" value (i.e. the number of leap seconds) to be supplied by the
caller. If AST__BAD is supplied for "Dtai", the internal look-up table of
leap seconds contained withn AST will be used. The conversions affected
are those between TAI and UTC, and those between TT and TDB.

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- A new method called astAxNorm has been added to the Frame class that
normalises an array of axis values. When used with SkyFrames, it allows
longitude values to be normalised into the shortest range.

- A bug has been fixed in the Fortran include file AST_PAR that caused constants
related to PI to be defined as single rather than double precision.

- A bug has been fixed in the astGetRegionBounds method that could
cause the wrong bounds to be returned for regions spanning a longitude =
zero singularity.

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- A new class of Mapping called UnitNormMap has been added that converts a
vector to a unit vector relative to a specified centre, plus length. A
UnitNormMap has N inputs and N+1 outputs.The lower N output coordinates
represent a unit vector parallel to the supplied input vector, and the
(N+1)'th output coordinate is the length of the input vector.

- The restriction that Mappings are immutable has been extended to all
Mapping classes. This means that attributes representing parameters of
a Mapping's forward or inverse transformation cannot be changed after
the Mapping has been created. In order to minimise the risk to existing
software, this rule does not apply to Mappings that have not yet been
included in other objects such as CmpMaps or FrameSets, or which have not
yet been cloned. In other words, an error is reported if an attempt is
made to change the nature of a Mapping's transformation, but only if the
reference count of the Mapping is greater than one. The Mapping classes
affected include: GrismMap, LutMap, PcdMap, SphMap, WcsMap and ZoomMap.

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- The configure script has a new option "--without-fortran" that allows
AST to be built in situations where no Fortran compiler is available. The
resulting library has no Fortran interface and so cannot be used within
Fortran applications. Also, the link scripts do not attempt to include the
fortran runtime libraries.

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- A bug in FitsChan has been fixed which could cause a small shift in
spectral axis value when writing out a spectral cube to FITS-WCS headers,
This shift occurred only if the celestial axes in the cube were not FK5
(RA,Dec).

- Avoid some more compiler warnings.

- A "BadKeyValue" warning is now issued by the FitsChan class if an illegal
FITS keyword value is encountered. See attribute "Warnings" and function
"astWarnings".