FITSWCSAPIMixin

class astropy.wcs.wcsapi.fitswcs.FITSWCSAPIMixin[source]

Bases: astropy.wcs.wcsapi.BaseLowLevelWCS, astropy.wcs.wcsapi.HighLevelWCSMixin

A mix-in class that is intended to be inherited by the WCS class and provides the low- and high-level WCS API

Attributes Summary

array_shape

The shape of the data that the WCS applies to as a tuple of length pixel_n_dim in (row, column) order (the convention for arrays in Python).

axis_correlation_matrix

Returns an (world_n_dim, pixel_n_dim) matrix that indicates using booleans whether a given world coordinate depends on a given pixel coordinate.

pixel_bounds

The bounds (in pixel coordinates) inside which the WCS is defined, as a list with pixel_n_dim (min, max) tuples.

pixel_n_dim

The number of axes in the pixel coordinate system.

pixel_shape

The shape of the data that the WCS applies to as a tuple of length pixel_n_dim in (x, y) order (where for an image, x is the horizontal coordinate and y is the vertical coordinate).

serialized_classes

Indicates whether Python objects are given in serialized form or as actual Python objects.

world_axis_names

An iterable of strings describing the name for each world axis.

world_axis_object_classes

A dictionary giving information on constructing high-level objects for the world coordinates.

world_axis_object_components

A list with world_n_dim elements giving information on constructing high-level objects for the world coordinates.

world_axis_physical_types

An iterable of strings describing the physical type for each world axis.

world_axis_units

An iterable of strings given the units of the world coordinates for each axis.

world_n_dim

The number of axes in the world coordinate system.

Methods Summary

array_index_to_world_values(*indices)

Convert array indices to world coordinates.

pixel_to_world_values(*pixel_arrays)

Convert pixel coordinates to world coordinates.

world_to_array_index_values(*world_arrays)

Convert world coordinates to array indices.

world_to_pixel_values(*world_arrays)

Convert world coordinates to pixel coordinates.

Attributes Documentation

array_shape
axis_correlation_matrix
pixel_bounds
pixel_n_dim
pixel_shape
serialized_classes
world_axis_names
world_axis_object_classes
world_axis_object_components
world_axis_physical_types
world_axis_units
world_n_dim

Methods Documentation

array_index_to_world_values(*indices)[source]

Convert array indices to world coordinates.

This is the same as pixel_to_world_values except that the indices should be given in (i, j) order, where for an image i is the row and j is the column (i.e. the opposite order to pixel_to_world_values).

If world_n_dim is 1, this method returns a single scalar or array, otherwise a tuple of scalars or arrays is returned.

pixel_to_world_values(*pixel_arrays)[source]

Convert pixel coordinates to world coordinates.

This method takes pixel_n_dim scalars or arrays as input, and pixel coordinates should be zero-based. Returns world_n_dim scalars or arrays in units given by world_axis_units. Note that pixel coordinates are assumed to be 0 at the center of the first pixel in each dimension. If a pixel is in a region where the WCS is not defined, NaN can be returned. The coordinates should be specified in the (x, y) order, where for an image, x is the horizontal coordinate and y is the vertical coordinate.

If world_n_dim is 1, this method returns a single scalar or array, otherwise a tuple of scalars or arrays is returned.

world_to_array_index_values(*world_arrays)[source]

Convert world coordinates to array indices.

This is the same as world_to_pixel_values except that the indices should be returned in (i, j) order, where for an image i is the row and j is the column (i.e. the opposite order to pixel_to_world_values). The indices should be returned as rounded integers.

If pixel_n_dim is 1, this method returns a single scalar or array, otherwise a tuple of scalars or arrays is returned.

world_to_pixel_values(*world_arrays)[source]

Convert world coordinates to pixel coordinates.

This method takes world_n_dim scalars or arrays as input in units given by world_axis_units. Returns pixel_n_dim scalars or arrays. Note that pixel coordinates are assumed to be 0 at the center of the first pixel in each dimension. If a world coordinate does not have a matching pixel coordinate, NaN can be returned. The coordinates should be returned in the (x, y) order, where for an image, x is the horizontal coordinate and y is the vertical coordinate.

If pixel_n_dim is 1, this method returns a single scalar or array, otherwise a tuple of scalars or arrays is returned.