mocpy.WCS¶

class mocpy.WCS(fig, fov, center=<SkyCoord (ICRS): (ra, dec) in deg (0., 0.)>, coordsys='icrs', projection='AIT', rotation=<Angle 0. rad>)[source]¶

Create a WCS for visualizing a MOC in a matplotlib axis.

This method is a quick astropy WCS instantiation and does not fit every use case. It is especially not designed for all-sky plots.

Parameters:

figfigure: The matplotlib figure used for plotting the MOC.
fovQuantity or Sequence[Quantity, Quantity]: Size of the field of view. If it is a sequence, it must be of length 2 and represent the longitudinal and latitudinal field of views.
centerSkyCoord, optional: World coordinates matching with the center of the plot. Default to (0 deg, 0 deg) (in ICRS frame).
coordsysstr, optional: Coordinate system. Default to “icrs”. Must be in [“icrs”, “galactic”].
projectionstr, optional: World base -> Image base projection type. See http://docs.astropy.org/en/stable/wcs/#supported-projections for the projections currently supported in astropy. Default to Aitoff.
rotationAngle, optional: The angle of rotation. Default to no rotation.

Returns:

wcsWCS: The WCS that can be passed to mocpy.MOC.fill/border.

Examples

>>> from mocpy import MOC, WCS
>>> from astropy.coordinates import Angle, SkyCoord
>>> import matplotlib.pyplot as plt
>>> import astropy.units as u
>>> # Create a MOC
>>> moc = MOC.from_elliptical_cone(lon = 0 * u.rad,
...                                lat = 0 * u.rad,
...                                a = 50 * u.deg,
...                                b = 20 * u.deg,
...                                pa = 90 * u.deg,
...                                max_depth = 13,
...                                )
>>> fig = plt.figure(figsize=(10, 10))
>>> with WCS(fig,
...           fov=200 * u.deg,
...           center=SkyCoord(0, 20, unit='deg', frame='icrs'),
...           coordsys="icrs",
...           rotation=Angle(0, u.degree),
...           projection="AIT") as wcs: wcs = wcs
>>> ax = fig.add_subplot(projection=wcs)
>>> # Call fill with a matplotlib axe and the `~astropy.wcs.WCS` wcs object.
>>> moc.fill(ax=ax, wcs=wcs, alpha=0.5, fill=True, color="green")
>>> moc.border(ax=ax, wcs=wcs, alpha=0.5, color="black")

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mocpy.WCS¶