ResampledLowLevelWCS#
- class ndcube.wcs.wrappers.ResampledLowLevelWCS(wcs, factor, offset=0)[source]#
Bases:
BaseWCSWrapper
A wrapper for a low-level WCS object that has down- or up-sampled pixel axes.
- Parameters:
wcs (
BaseLowLevelWCS
) – The original WCS for which to reorder axesfactor (
int
orfloat
or iterable of the same) – The factor by which to increase the pixel size for each pixel axis. If a scalar, the same factor is used for all axes.offset (
int
orfloat
or iterable of the same) – The location on the underlying pixel grid which corresponds to zero on the top level pixel grid. If a scalar, the grid will be shifted by the same amount in all dimensions.
Attributes Summary
The bounds (in pixel coordinates) inside which the WCS is defined, as a list with
pixel_n_dim
(min, max)
tuples.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 andy
is the vertical coordinate).Methods Summary
pixel_to_world_values
(*pixel_arrays)Convert pixel coordinates to world coordinates.
world_to_pixel_values
(*world_arrays)Convert world coordinates to pixel coordinates.
Attributes Documentation
- pixel_bounds#
- pixel_shape#
Methods Documentation
- 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. Returnsworld_n_dim
scalars or arrays in units given byworld_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 should be returned. The coordinates should be specified in the(x, y)
order, where for an image,x
is the horizontal coordinate andy
is the vertical coordinate.If
world_n_dim
is1
, 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 byworld_axis_units
. Returnspixel_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 should be returned. The coordinates should be returned in the(x, y)
order, where for an image,x
is the horizontal coordinate andy
is the vertical coordinate.If
pixel_n_dim
is1
, this method returns a single scalar or array, otherwise a tuple of scalars or arrays is returned.