Source code for sunpy.visualization.wcsaxes_compat

This module provides functions to make WCSAxes work in SunPy.
import matplotlib.pyplot as plt
from packaging.version import Version

import astropy.units as u
from astropy import __version__ as astropy_version
from astropy.visualization import wcsaxes

from sunpy.coordinates import HeliographicCarrington, HeliographicStonyhurst

__all__ = ["is_wcsaxes", "gca_wcs", "get_world_transform",
           "default_wcs_grid", "wcsaxes_heliographic_overlay"]

[docs] def is_wcsaxes(axes): """ Tests a `matplotlib.axes.Axes` object to see if it is an instance of `~astropy.visualization.wcsaxes.WCSAxes`. Parameters ---------- axes : `matplotlib.axes` Axes to test. Returns ------- `bool` Result of the test. """ return isinstance(axes, wcsaxes.WCSAxes)
[docs] def gca_wcs(wcs, fig=None, slices=None): """ Get the current axes, or create a new `~astropy.visualization.wcsaxes.WCSAxes` if ``fig`` has no axes. Parameters ---------- wcs : `astropy.wcs.WCS` A `~astropy.wcs.WCS` object used to create a new axes. fig : `matplotlib.figure.Figure` The figure in which to check for the axes. If ``None``, the current figure is used (or a new one created if there are no current figures). slices : `tuple` ``slices`` is passed to `~astropy.visualization.wcsaxes.WCSAxes` to describe which two dimensions of the `~astropy.wcs.WCS` object are being plotted. This slices the multidimensional wcs object in the way it needs to be sliced. Returns ------- `matplotlib.axes.Axes` or `~astropy.visualization.wcsaxes.WCSAxes` The current axes, or a new one if created. """ if not fig: fig = plt.gcf() if not len(fig.get_axes()): ax = plt.axes(projection=wcs, slices=slices) else: ax = plt.gca() return ax
[docs] def get_world_transform(axes): """ Get the transformation to world coordinates. If the axes is a `~astropy.visualization.wcsaxes.WCSAxes` instance this returns the transform to the "world" coordinates, otherwise it returns the transform to the matplotlib data coordinates, which are assumed to be in world coordinates. Parameters ---------- axes : `~astropy.visualization.wcsaxes.WCSAxes` or `~matplotlib.axes.Axes` The axes to get the transform from. Returns ------- `~matplotlib.transforms.CompositeGenericTransform` The transformation object. """ if is_wcsaxes(axes): transform = axes.get_transform('world') else: transform = axes.transData return transform
[docs] def default_wcs_grid(axes): """ Apply some default `~astropy.visualization.wcsaxes.WCSAxes` grid formatting. Parameters ---------- axes : `~astropy.visualization.wcsaxes.WCSAxes` The `~astropy.visualization.wcsaxes.WCSAxes` object to draw the world coordinate grid on. """ axes.coords.grid(color='white', alpha=0.6, linestyle='dotted', linewidth=0.5)
[docs] @u.quantity_input def wcsaxes_heliographic_overlay(axes, grid_spacing: u.deg = 10*u.deg, annotate=True, obstime=None, rsun=None, observer=None, system='stonyhurst', **kwargs): """ Create a heliographic overlay using `~astropy.visualization.wcsaxes.WCSAxes`. Will draw a grid and label the top axes. Parameters ---------- axes : `~astropy.visualization.wcsaxes.WCSAxes` The `~astropy.visualization.wcsaxes.WCSAxes` object to create the overlay on. grid_spacing: `~astropy.units.Quantity` Spacing for longitude and latitude grid in degrees. annotate : `bool` Passing `False` disables the axes labels and the ticks on the top and right axes. obstime : `~astropy.time.Time` The ``obstime`` to use for the grid coordinate frame. rsun : `~astropy.units.Quantity` The ``rsun`` to use for the grid coordinate frame. observer : `~astropy.coordinates.SkyCoord` The ``observer`` to use for the grid coordinate frame. Only used for Carrington coordinates. system : str Coordinate system for the grid. Must be 'stonyhurst' or 'carrington'. If 'carrington', the ``observer`` keyword argument must be specified. kwargs : Additional keyword arguments are passed to :meth:`astropy.visualization.wcsaxes.CoordinateHelper.grid`. Returns ------- `~astropy.visualization.wcsaxes.WCSAxes` The overlay object. Notes ----- Keywords are passed to `~astropy.visualization.wcsaxes.coordinates_map.CoordinatesMap.grid`. """ # Unpack spacing if isinstance(grid_spacing, u.Quantity) and grid_spacing.size == 1: lon_space = lat_space = grid_spacing elif grid_spacing.size == 2: lon_space, lat_space = grid_spacing else: raise ValueError("grid_spacing must be a Quantity of length one or two.") if system == 'stonyhurst': overlay = axes.get_coords_overlay(HeliographicStonyhurst( obstime=obstime, rsun=rsun)) elif system == 'carrington': overlay = axes.get_coords_overlay(HeliographicCarrington( obstime=obstime, observer=observer, rsun=rsun)) else: raise ValueError(f"system must be 'stonyhurst' or 'carrington' (got '{system}')") # Set the native coordinates to be bottom and left only so they don't share # axes with the overlay. c1, c2 = axes.coords c1.set_ticks_position('bl') c2.set_ticks_position('bl') lon = overlay[0] lat = overlay[1] # TODO: Remove when we depend on astropy 5.3 if Version(astropy_version) >= Version(""): lon.coord_wrap = 180 * u.deg else: lon.coord_wrap = 180 lon.set_major_formatter('dd') if annotate: lon.set_axislabel(f'{system.capitalize()} Longitude', minpad=0.8) lat.set_axislabel(f'{system.capitalize()} Latitude', minpad=0.9) lon.set_ticks_position('tr') lat.set_ticks_position('tr') else: lat.set_ticks_visible(False) lon.set_ticks_visible(False) lat.set_ticklabel_visible(False) lon.set_ticklabel_visible(False) grid_kw = {'color': 'white', 'zorder': 100, 'alpha': 0.5} grid_kw.update(kwargs) # Don't plot white ticks by default (only if explicitly asked) tick_color = grid_kw['color'] if 'color' in kwargs else 'k' lon.set_ticks(spacing=lon_space, color=tick_color) lat.set_ticks(spacing=lat_space, color=tick_color) overlay.grid(**grid_kw) if axes.title: x, y = axes.title.get_position() axes.title.set_position([x, y + 0.08]) return overlay