GWCS 0.17.0

New Features

• wcs_from_points now includes fitting for the inverse transform. [#349]
• Generalized WCS.to_fits_sip to be able to create a 2D celestial FITS WCS from celestial subspace of the WCS. Also, now WCS.to_fits_sip` supports arbitrary order of output axes. [#357]

API Changes

• Modified interface to wcs_from_points function to better match analogous function in astropy. [#349]
• Model._BoundingBox was renamed to ``Model.ModelBoundingBox`. [#376, #377]

Bug Fixes

• world_axis_object_components and world_axis_object_classes now ensure unique keys in CompositeFrame and CoordinateFrame. [#356]
• Fix issue where RuntimeWarning is raised when there are NaNs in coordinates in angle wrapping code [#367]
• Fix deprecation warning when wcs is initialized with a pipeline [#368]
• Use CD formalism in WCS.to_fits_sip(). [#380]

0.16.1

taggging release 0.16.1

GWCS 0.16.0

New Features

• Added an option to to_fits_sip() to be able to specify the reference point (crpix) of the FITS WCS. [#337]
• Added support for providing custom range of degrees in to_fits_sip. [#339]

Bug Fixes

• Bounding_box now works with tuple of Quantities. [#331]
• Fix a formula for estimating crpix in to_fits_sip() so that crpix is near the center of the bounding box. [#337]
• Allow sub-pixel sampling of the WCS model when computing SIP approximation in to_fits_sip(). [#338]
• Fixed a bug in to_fits_sip due to which inv_degree was ignored. [#339]

GWCS 0.15.0

New Features

• Added insert_frame method to modify the pipeline of a WCS object. [#299]
• Added to_fits_tab method to generate FITS header and binary table extension following FITS WCS -TAB convention. [#295]
• Added in_image function for testing whether a point in world coordinates maps back to the domain of definition of the forward transformation. [#322]
• Implemented iterative inverse for imaging WCS. [#324]

GWCS 0.14.0

New Features

• Updated versions of schemas for gwcs objects based on latest versions of transform schemas in asdf-standard. [#307]
• Added a wcs.Step class to allow serialization to ASDF to use references. [#317]
• WCS.pipeline now is a list of Step instances instead of a (frame, transform) tuple. Use WCS.pipeline.transform and WCS.pipeline.frame to access them. [#319]

Bug Fixes

• Fix a bug in polygon fill for zero-width bounding boxes. [#293]
• Add an optional parameter input_frame to ``wcstools.wcs_from_fiducial`. [#312]

GWCS 0.13.0

New Features

• Added two new transforms - SphericalToCartesian and CartesianToSpherical
• Added to_fits_sip method to generate FITS header with SIP keywords
• Added get_ctype_from_ucd function

Bug Fixes

• Fixed an off by one issue in utils.make_fitswcs_transform

GWCS 0.12.0

New Features

• Added a method fix_inputs which rturns an unique WCS from a compound WCS by fixing inputs.
• Update the StokesFrame to work for arrays of coordinates and integrate with APE 14.
• Added support for world_axis_names, pixel_axis_names, world_axis_object_components and
  world_axis_object_classes properties on LowLevelWCS objects.
• Added new transforms - ToDirectionCosines, FromDirectionCosines, WavelengthFromGratingEquation, AnglesFromGratingEquation3D, Snell3D, SellmeierGlass and SellmeierZemax.
• Removed astropy-helpers.

See CHANGES.rst for the full list of changes.

GWCS 0.11

New Features

- Add a schema and tag for the Stokes frame. 
- Added WCS.pixel_shape property. 

Bug Fixes

- Update util.isnumerical(...) to recognize big-endian types as numeric.
- Fixed issue in unified WCS API (APE14) for transforms that use Quantity.
- Fixed WCS API issues when output_frame is 1D, e.g. Spectral only.

GWCS v0.10.0

GWCS v0.10.0 requires astropy v3.1.

New Features:

• Implement support for astropy APE 14 (https://doi.org/10.5281/zenodo.1188875).
• Added a wcs_from_points function which creates a WCS object from two matching sets of points (x,y) and (ra, dec).
• Added a TemporalFrame to represent relative or absolute time axes.
• Removed deprecated grid_from_domain function and WCS.domain property.
• Added a StokesFrame which converts from 'I', 'Q', 'U', 'V' to 0-3.
• Generalized the footrpint calculation to all output axes.

Bug Fixes:

• Initializing a WCS object with a pipeline list now keeps the complete CoordinateFrame objects in the WCS.pipeline. The effect is that a WCS object can now be initialized with a pipeline from a different WCS object.
• Fixed a bug in bounding_box definition when the WCS has only one axis.
• Fixed a bug in grid_from_bounding_box which caused the grid to be larger than the image in cases when the bounding box is on the edges of an image.

GWCS v0.8.0

Changes:

• LabelMapperRange now returns LabelMapperRange._no_label when the key is
  not within any range. [#71]

• LabelMapperDict now returns LabelMapperDict._no_label when the key does
  not match. [#72]

• Replaced domain with bounding_box. [#74]

• Added a LabelMapper model where mapper is an instance of
  ~astropy.modeling.core.Model. [#78]

• Evaluating a WCS with bounding box was moved to astropy.modeling. [#86]

• RegionsSelector now handles the case when a label does not have a corresponding
  transform and returns RegionsSelector.undefined_transform_value. [#86]

• GWCS now deals with axes types which are neither celestial nor spectral as "unknown"
  and creates a transform equivalent to the FITS linear transform. [#92]