New Features
This is a brief overview of the new features included in Astropy 0.2–please
see the “What’s New” section of the documentation for more details.
astropy.coordinates
- This new subpackage contains a representation of celestial coordinates,
and provides a wide range of related functionality. While
fully-functional, it is a work in progress and parts of the API may
change in subsequent releases.
astropy.cosmology
- Update to include cosmologies with variable dark energy equations of state.
(This introduces some API incompatibilities with the older Cosmology
objects).
- Added parameters for relativistic species (photons, neutrinos) to the
astropy.cosmology classes. The current treatment assumes that neutrinos are
massless. [#365]
astropy.table I/O infrastructure for custom readers/writers
implemented. [#305]
- Added support for reading/writing HDF5 files [#461]
New astropy.time sub-package. [#332]
New astropy.units sub-package that includes a class for units
(astropy.units.Unit) and scalar quantities that have units
(astropy.units.Quantity). [#370, #445]
This has the following effects on other sub-packages:
- In astropy.wcs, the wcs.cunit list now takes and returns
astropy.units.Unit objects. [#379]
- In astropy.nddata, units are now stored as astropy.units.Unit
objects. [#382]
- In astropy.table, units on columns are now stored as
astropy.units.Unit objects. [#380]
- In astropy.constants, constants are now stored as
astropy.units.Quantity objects. [#529]
astropy.io.ascii
- Improved integration with the astropy.table Table class so that
table and column metadata (e.g. keywords, units, description,
formatting) are directly available in the output table object. The
CDS, DAOphot, and IPAC format readers now provide this type of
integrated metadata.
- Changed to using astropy.table masked tables instead of NumPy
masked arrays for tables with missing values.
- Added SExtractor table reader to astropy.io.ascii [#420]
- Removed the Memory reader class which was used to convert data input
passed to the write function into an internal table. Instead
write instantiates an astropy Table object using the data
input to write.
- Removed the NumpyOutputter as the output of reading a table is now
always a Table object.
- Removed the option of supplying a function as a column output
formatter.
- Added a new strip_whitespace keyword argument to the write
function. This controls whether whitespace is stripped from
the left and right sides of table elements before writing.
Default is True.
- Fixed a bug in reading IPAC tables with null values.
Added support for masked tables with missing or invalid data [#451]
astropy.wcs
- From updating the the underlying wcslib 4.16:
- When astropy.wcs.WCS constructs a default coordinate
representation it will give it the special name “DEFAULTS”, and
will not report “Found one coordinate representation”.