Source code for gammapy.visualization.panel

# Licensed under a 3-clause BSD style license - see LICENSE.rst
"""Helper functions and functions for plotting gamma-ray images."""
import numpy as np
from astropy.coordinates import Angle

__all__ = ["MapPanelPlotter"]

__doctest_requires__ = {("colormap_hess", "colormap_milagro"): ["matplotlib"]}

[docs]class MapPanelPlotter: """ Map panel plotter class. Given a `~matplotlib.pyplot.Figure` object this class creates axes objects using `~matplotlib.gridspec.GridSpec` and plots a given sky map onto these. Parameters ---------- figure : `~matplotlib.pyplot.figure.` Figure instance. xlim : `~astropy.coordinates.Angle` Angle object specifying the longitude limits. ylim : `~astropy.coordinates.Angle` Angle object specifying the latitude limits. npanels : int Number of panels. **kwargs : dict Keyword arguments passed to `~matplotlib.gridspec.GridSpec`. """ def __init__(self, figure, xlim, ylim, npanels=4, **kwargs): from matplotlib.gridspec import GridSpec self.figure = figure self.parameters = {"xlim": xlim, "ylim": ylim, "npanels": npanels} self.grid_spec = GridSpec(nrows=npanels, ncols=1, **kwargs) def _get_ax_extend(self, ax, panel): """Get width and height of the axis in world coordinates.""" p = self.parameters # compute aspect ratio of the axis aspect = ax.bbox.width / ax.bbox.height # compute width and height in world coordinates height = np.abs(p["ylim"].diff()) width = aspect * height left, bottom = p["xlim"][0].wrap_at("180d"), p["ylim"][0] width_all = np.abs(p["xlim"].wrap_at("180d").diff()) xoverlap = ((p["npanels"] * width) - width_all) / (p["npanels"] - 1.0) if xoverlap < 0: raise ValueError( "No overlap between panels. Please reduce figure " "height or increase vertical space between the panels." ) left = left - panel * (width - xoverlap) return left[0], bottom, width, height def _set_ax_fov(self, ax, panel): left, bottom, width, height = self._get_ax_extend(ax, panel) # set fov xlim = Angle([left, left - width]) ylim = Angle([bottom, bottom + height]) xlim_pix, ylim_pix = ax.wcs.wcs_world2pix(xlim.deg, ylim.deg, 1) ax.set_xlim(*xlim_pix) ax.set_ylim(*ylim_pix) return ax
[docs] def plot_panel(self, map, panel=1, panel_fov=None, **kwargs): """ Plot sky map on one panel. Parameters ---------- map : `~gammapy.maps.WcsNDMap` Map to plot. panel : int Which panel to plot on (counted from top). """ if panel_fov is None: panel_fov = panel spec = self.grid_spec[panel] ax = self.figure.add_subplot(spec, projection=map.geom.wcs) try: ax = map.plot(ax=ax, **kwargs) except AttributeError: ax = map.plot_rgb(ax=ax, **kwargs) ax = self._set_ax_fov(ax, panel_fov) return ax
[docs] def plot(self, map, **kwargs): """ Plot sky map on all panels. Parameters ---------- map : `~gammapy.maps.WcsNDMap` Map to plot. """ p = self.parameters axes = [] for panel in range(p["npanels"]): ax = self.plot_panel(map, panel=panel, **kwargs) axes.append(ax) return axes