ExtraCoordsABC#
- class ndcube.ExtraCoordsABC[source]#
Bases:
ABC
A representation of additional world coordinates associated with pixel axes.
ExtraCoords can be initialised by either specifying a
BaseLowLevelWCS
object and amapping
, or it can be built up by specifying one or more lookup tables.- Parameters:
wcs – The WCS specifying the extra coordinates.
mapping – The mapping between the array dimensions and pixel dimensions in the extra coords object. This is an iterable of
(array_dimension, pixel_dimension)
pairs of length equal to the number of pixel dimensions in the extra coords.
Attributes Summary
Return True if no extra coords present, else return False.
The mapping between the array dimensions and pixel dimensions.
A WCS object representing the world coordinates described by this
ExtraCoords
.Methods Summary
add
(name, array_dimension, lookup_table[, ...])Add a coordinate to this
ExtraCoords
based on a lookup table.keys
()The world axis names for all the coordinates in the extra coords.
Attributes Documentation
- is_empty#
Return True if no extra coords present, else return False.
- mapping#
The mapping between the array dimensions and pixel dimensions.
This is an iterable of
(array_dimension, pixel_dimension)
pairs of length equal to the number of pixel dimensions in the extra coords.
- wcs#
A WCS object representing the world coordinates described by this
ExtraCoords
.Note
This WCS object does not map to the pixel dimensions of the data array in the
NDCube
object. It only includes pixel dimensions associated with the extra coordinates. For example, if there is only one extra coordinate associated with a single pixel dimension, this WCS will only have 1 pixel dimension, even if theNDCube
object has a data array of 2-D or greater. Therefore using this WCS directly might lead to some confusing results.
Methods Documentation
- abstract add(name: str | Iterable[str], array_dimension: int | Iterable[int], lookup_table: Any, physical_types: str | Iterable[str] = None, **kwargs)[source]#
Add a coordinate to this
ExtraCoords
based on a lookup table.- Parameters:
name (
str
or sequence ofstr
) – The name(s) for these world coordinate(s).array_dimension (
int
ortuple
ofint
) – The array dimension(s), to which this lookup table corresponds.lookup_table (
object
or sequence ofobject
) – The lookup table. ABaseTableCoordinate
subclass or anything that can instantiate one, i.e. currently aTime
,SkyCoord
, or a (sequence of)Quantity
.physical_types (
str
or iterable ofstr
, optional) – Descriptor(s) of the <dimensions and physical types associated with each axis; length must match the number of dimensions inlookup_table
.