Simplify "artist reference" example.

In particular, add each artist directly to its own axes, instead of
shifting each of them by some offset and grouping all of them together
in a PatchCollection.  Note that this makes the example no longer
showcase the use of PatchCollection, but at least based on the docstring
that was not the intent of the example anyways, and PatchCollection is
showcased elsewhere (in the patch_collection.py example, in particular).

Author: anntzer

examples/shapes_and_collections/artist_reference.py

@@ -3,66 +3,25 @@
 Reference for Matplotlib artists
 ================================
 
-This example displays several of Matplotlib's graphics primitives (artists)
-drawn using matplotlib API. A full list of artists and the documentation is
-available at :ref:`the artist API <artist-api>`.
+This example displays several of Matplotlib's graphics primitives (artists).
+A full list of artists is documented at :ref:`the artist API <artist-api>`.
+
+See also :doc:`/gallery/shapes_and_collections/patch_collection`, which groups
+all artists into a single `.PatchCollection` instead.
 
 Copyright (c) 2010, Bartosz Telenczuk
 BSD License
 """
-import matplotlib.pyplot as plt
-import numpy as np
-import matplotlib.path as mpath
+
+import matplotlib as mpl
 import matplotlib.lines as mlines
 import matplotlib.patches as mpatches
-from matplotlib.collections import PatchCollection
-
-
-def label(xy, text):
-    y = xy[1] - 0.15  # shift y-value for label so that it's below the artist
-    plt.text(xy[0], y, text, ha="center", family='sans-serif', size=14)
-
-
-fig, ax = plt.subplots()
-# create 3x3 grid to plot the artists
-grid = np.mgrid[0.2:0.8:3j, 0.2:0.8:3j].reshape(2, -1).T
-
-patches = []
-
-# add a circle
-circle = mpatches.Circle(grid[0], 0.1, ec="none")
-patches.append(circle)
-label(grid[0], "Circle")
-
-# add a rectangle
-rect = mpatches.Rectangle(grid[1] - [0.025, 0.05], 0.05, 0.1, ec="none")
-patches.append(rect)
-label(grid[1], "Rectangle")
-
-# add a wedge
-wedge = mpatches.Wedge(grid[2], 0.1, 30, 270, ec="none")
-patches.append(wedge)
-label(grid[2], "Wedge")
-
-# add a Polygon
-polygon = mpatches.RegularPolygon(grid[3], 5, radius=0.1)
-patches.append(polygon)
-label(grid[3], "Polygon")
-
-# add an ellipse
-ellipse = mpatches.Ellipse(grid[4], 0.2, 0.1)
-patches.append(ellipse)
-label(grid[4], "Ellipse")
-
-# add an arrow
-arrow = mpatches.Arrow(grid[5, 0] - 0.05, grid[5, 1] - 0.05, 0.1, 0.1,
-                       width=0.1)
-patches.append(arrow)
-label(grid[5], "Arrow")
+import matplotlib.path as mpath
+import matplotlib.pyplot as plt
 
-# add a path patch
+# Prepare the data for the PathPatch below.
 Path = mpath.Path
-path_data = [
+codes, verts = zip(*[
     (Path.MOVETO, [0.018, -0.11]),
     (Path.CURVE4, [-0.031, -0.051]),
     (Path.CURVE4, [-0.115, 0.073]),
@@ -71,35 +30,28 @@ def label(xy, text):
     (Path.CURVE4, [0.043, 0.121]),
     (Path.CURVE4, [0.075, -0.005]),
     (Path.CURVE4, [0.035, -0.027]),
-    (Path.CLOSEPOLY, [0.018, -0.11])]
-codes, verts = zip(*path_data)
-path = mpath.Path(verts + grid[6], codes)
-patch = mpatches.PathPatch(path)
-patches.append(patch)
-label(grid[6], "PathPatch")
-
-# add a fancy box
-fancybox = mpatches.FancyBboxPatch(
-    grid[7] - [0.025, 0.05], 0.05, 0.1,
-    boxstyle=mpatches.BoxStyle("Round", pad=0.02))
-patches.append(fancybox)
-label(grid[7], "FancyBboxPatch")
-
-# add a line
-x, y = ([-0.06, 0.0, 0.1], [0.05, -0.05, 0.05])
-line = mlines.Line2D(x + grid[8, 0], y + grid[8, 1], lw=5., alpha=0.3)
-label(grid[8], "Line2D")
-
-colors = np.linspace(0, 1, len(patches))
-collection = PatchCollection(patches, cmap=plt.cm.hsv, alpha=0.3)
-collection.set_array(colors)
-ax.add_collection(collection)
-ax.add_line(line)
-
-plt.axis('equal')
-plt.axis('off')
-plt.tight_layout()
-
+    (Path.CLOSEPOLY, [0.018, -0.11])])
+
+artists = [
+    mpatches.Circle((0, 0), 0.1, ec="none"),
+    mpatches.Rectangle((-0.025, -0.05), 0.05, 0.1, ec="none"),
+    mpatches.Wedge((0, 0), 0.1, 30, 270, ec="none"),
+    mpatches.RegularPolygon((0, 0), 5, radius=0.1),
+    mpatches.Ellipse((0, 0), 0.2, 0.1),
+    mpatches.Arrow(-0.05, -0.05, 0.1, 0.1, width=0.1),
+    mpatches.PathPatch(mpath.Path(verts, codes), ec="none"),
+    mpatches.FancyBboxPatch((-0.025, -0.05), 0.05, 0.1, ec="none",
+                            boxstyle=mpatches.BoxStyle("Round", pad=0.02)),
+    mlines.Line2D([-0.06, 0.0, 0.1], [0.05, -0.05, 0.05], lw=5),
+]
+
+axs = plt.figure(figsize=(6, 6), layout="constrained").subplots(3, 3)
+for i, (ax, artist) in enumerate(zip(axs.flat, artists)):
+    artist.set(color=mpl.colormaps["hsv"](i / len(artists)))
+    ax.add_artist(artist)
+    ax.set(title=type(artist).__name__,
+           aspect=1, xlim=(-.2, .2), ylim=(-.2, .2))
+    ax.set_axis_off()
 plt.show()
 
 #############################################################################
@@ -122,8 +74,4 @@ def label(xy, text):
 #    - `matplotlib.patches.PathPatch`
 #    - `matplotlib.patches.FancyBboxPatch`
 #    - `matplotlib.patches.RegularPolygon`
-#    - `matplotlib.collections`
-#    - `matplotlib.collections.PatchCollection`
-#    - `matplotlib.cm.ScalarMappable.set_array`
-#    - `matplotlib.axes.Axes.add_collection`
-#    - `matplotlib.axes.Axes.add_line`
+#    - `matplotlib.axes.Axes.add_artist`

examples/shapes_and_collections/patch_collection.py

@@ -4,6 +4,9 @@
 ============================
 
 This example demonstrates how to use `.collections.PatchCollection`.
+
+See also :doc:`/gallery/shapes_and_collections/artist_reference`, which instead
+adds each artist separately to its own axes.
 """
 
 import numpy as np