class astropy.visualization.wcsaxes.CoordinatesMap(axes, transform=None, coord_meta=None, frame_class=<class 'astropy.visualization.wcsaxes.frame.RectangularFrame'>, previous_frame_path=None)[source]#

Bases: object

A container for coordinate helpers that represents a coordinate system.

This object can be used to access coordinate helpers by index (like a list) or by name (like a dictionary).


The axes the coordinate map belongs to.

transformTransform, optional

The transform for the data.

coord_metadict, optional

A dictionary providing additional metadata. This should include the keys type, wrap, and unit. Each of these should be a list with as many items as the dimension of the coordinate system. The type entries should be one of longitude, latitude, or scalar, the wrap entries should give, for the longitude, the angle at which the coordinate wraps (and None otherwise), and the unit should give the unit of the coordinates as Unit instances. This can optionally also include a format_unit entry giving the units to use for the tick labels (if not specified, this defaults to unit).

frame_classtype, optional

The class for the frame, which should be a subclass of BaseFrame. The default is to use a RectangularFrame

previous_frame_pathPath, optional

When changing the WCS of the axes, the frame instance will change but we might want to keep re-using the same underlying matplotlib Path - in that case, this can be passed to this keyword argument.

Methods Summary


grid([draw_grid, grid_type])

Plot gridlines for both coordinates.


Methods Documentation

grid(draw_grid=True, grid_type=None, **kwargs)[source]#

Plot gridlines for both coordinates.

Standard matplotlib appearance options (color, alpha, etc.) can be passed as keyword arguments.


Whether to show the gridlines

grid_type{ ‘lines’ | ‘contours’ }

Whether to plot the contours by determining the grid lines in world coordinates and then plotting them in world coordinates ('lines') or by determining the world coordinates at many positions in the image and then drawing contours ('contours'). The first is recommended for 2-d images, while for 3-d (or higher dimensional) cubes, the 'contours' option is recommended. By default, ‘lines’ is used if the transform has an inverse, otherwise ‘contours’ is used.