Shorten demo_axes_grid example.

anntzer · anntzer · commit 9c05c31d90f9 · 2022-12-02T13:42:14.000+01:00
Get rid of the individual example functions, as they are not really
independent from one another anyways (given that they use absolute
subplot positioning onto the main figure).  This also allows not having
to reload the sample data in each function, and thus concentrate more on
showcasing the ImageGrid functionality.

Group some kwargs to ImageGrid in a single line; e.g. the cbar arguments
clearly logically belong together.
diff --git a/examples/axes_grid1/demo_axes_grid.py b/examples/axes_grid1/demo_axes_grid.py
@@ -3,123 +3,78 @@
 Demo Axes Grid
 ==============
 
-Grid of 2x2 images with single or own colorbar.
+Grid of 2x2 images with a single colorbar or with one colorbar per axes.
 """
 
 from matplotlib import cbook
 import matplotlib.pyplot as plt
 from mpl_toolkits.axes_grid1 import ImageGrid
 
 
-def get_demo_image():
-    z = cbook.get_sample_data("axes_grid/bivariate_normal.npy", np_load=True)
-    # z is a numpy array of 15x15
-    return z, (-3, 4, -4, 3)
-
-
-def demo_simple_grid(fig):
-    """
-    A grid of 2x2 images with 0.05 inch pad between images and only
-    the lower-left axes is labeled.
-    """
-    grid = ImageGrid(fig, 141,  # similar to subplot(141)
-                     nrows_ncols=(2, 2),
-                     axes_pad=0.05,
-                     label_mode="1",
-                     )
-    Z, extent = get_demo_image()
-    for ax in grid:
-        ax.imshow(Z, extent=extent)
-    # This only affects axes in first column and second row as share_all=False.
-    grid.axes_llc.set_xticks([-2, 0, 2])
-    grid.axes_llc.set_yticks([-2, 0, 2])
-
-
-def demo_grid_with_single_cbar(fig):
-    """
-    A grid of 2x2 images with a single colorbar
-    """
-    grid = ImageGrid(fig, 142,  # similar to subplot(142)
-                     nrows_ncols=(2, 2),
-                     axes_pad=0.0,
-                     share_all=True,
-                     label_mode="L",
-                     cbar_location="top",
-                     cbar_mode="single",
-                     )
-
-    Z, extent = get_demo_image()
-    for ax in grid:
-        im = ax.imshow(Z, extent=extent)
-    grid.cbar_axes[0].colorbar(im)
-
-    for cax in grid.cbar_axes:
-        cax.toggle_label(False)
-
-    # This affects all axes as share_all = True.
-    grid.axes_llc.set_xticks([-2, 0, 2])
-    grid.axes_llc.set_yticks([-2, 0, 2])
-
-
-def demo_grid_with_each_cbar(fig):
-    """
-    A grid of 2x2 images. Each image has its own colorbar.
-    """
-    grid = ImageGrid(fig, 143,  # similar to subplot(143)
-                     nrows_ncols=(2, 2),
-                     axes_pad=0.1,
-                     label_mode="1",
-                     share_all=True,
-                     cbar_location="top",
-                     cbar_mode="each",
-                     cbar_size="7%",
-                     cbar_pad="2%",
-                     )
-    Z, extent = get_demo_image()
-    for ax, cax in zip(grid, grid.cbar_axes):
-        im = ax.imshow(Z, extent=extent)
-        cax.colorbar(im)
-        cax.toggle_label(False)
-
-    # This affects all axes because we set share_all = True.
-    grid.axes_llc.set_xticks([-2, 0, 2])
-    grid.axes_llc.set_yticks([-2, 0, 2])
-
-
-def demo_grid_with_each_cbar_labelled(fig):
-    """
-    A grid of 2x2 images. Each image has its own colorbar.
-    """
-    grid = ImageGrid(fig, 144,  # similar to subplot(144)
-                     nrows_ncols=(2, 2),
-                     axes_pad=(0.45, 0.15),
-                     label_mode="1",
-                     share_all=True,
-                     cbar_location="right",
-                     cbar_mode="each",
-                     cbar_size="7%",
-                     cbar_pad="2%",
-                     )
-    Z, extent = get_demo_image()
-
-    # Use a different colorbar range every time
-    limits = ((0, 1), (-2, 2), (-1.7, 1.4), (-1.5, 1))
-    for ax, cax, vlim in zip(grid, grid.cbar_axes, limits):
-        im = ax.imshow(Z, extent=extent, vmin=vlim[0], vmax=vlim[1])
-        cb = cax.colorbar(im)
-        cb.set_ticks((vlim[0], vlim[1]))
-
-    # This affects all axes because we set share_all = True.
-    grid.axes_llc.set_xticks([-2, 0, 2])
-    grid.axes_llc.set_yticks([-2, 0, 2])
+Z = cbook.get_sample_data(  # (15, 15) array
+    "axes_grid/bivariate_normal.npy", np_load=True)
+extent = (-3, 4, -4, 3)
 
 
 fig = plt.figure(figsize=(10.5, 2.5))
 fig.subplots_adjust(left=0.05, right=0.95)
 
-demo_simple_grid(fig)
-demo_grid_with_single_cbar(fig)
-demo_grid_with_each_cbar(fig)
-demo_grid_with_each_cbar_labelled(fig)
+
+# A grid of 2x2 images with 0.05 inch pad between images and only the
+# lower-left axes is labeled.
+grid = ImageGrid(
+    fig, 141,  # similar to fig.add_subplot(141).
+     nrows_ncols=(2, 2), axes_pad=0.05, label_mode="1")
+for ax in grid:
+    ax.imshow(Z, extent=extent)
+# This only affects axes in first column and second row as share_all=False.
+grid.axes_llc.set_xticks([-2, 0, 2])
+grid.axes_llc.set_yticks([-2, 0, 2])
+
+
+# A grid of 2x2 images with a single colorbar
+grid = ImageGrid(
+    fig, 142,  # similar to fig.add_subplot(142).
+    nrows_ncols=(2, 2), axes_pad=0.0, label_mode="L", share_all=True,
+    cbar_location="top", cbar_mode="single")
+for ax in grid:
+    im = ax.imshow(Z, extent=extent)
+grid.cbar_axes[0].colorbar(im)
+for cax in grid.cbar_axes:
+    cax.toggle_label(False)
+# This affects all axes as share_all = True.
+grid.axes_llc.set_xticks([-2, 0, 2])
+grid.axes_llc.set_yticks([-2, 0, 2])
+
+
+# A grid of 2x2 images. Each image has its own colorbar.
+grid = ImageGrid(
+    fig, 143,  # similar to fig.add_subplot(143).
+    nrows_ncols=(2, 2), axes_pad=0.1, label_mode="1", share_all=True,
+    cbar_location="top", cbar_mode="each", cbar_size="7%", cbar_pad="2%")
+for ax, cax in zip(grid, grid.cbar_axes):
+    im = ax.imshow(Z, extent=extent)
+    cax.colorbar(im)
+    cax.toggle_label(False)
+# This affects all axes because we set share_all = True.
+grid.axes_llc.set_xticks([-2, 0, 2])
+grid.axes_llc.set_yticks([-2, 0, 2])
+
+
+# A grid of 2x2 images. Each image has its own colorbar.
+grid = ImageGrid(
+    fig, 144,  # similar to fig.add_subplot(144).
+    nrows_ncols=(2, 2), axes_pad=(0.45, 0.15), label_mode="1", share_all=True,
+    cbar_location="right", cbar_mode="each", cbar_size="7%", cbar_pad="2%")
+# Use a different colorbar range every time
+limits = ((0, 1), (-2, 2), (-1.7, 1.4), (-1.5, 1))
+for ax, cax, vlim in zip(grid, grid.cbar_axes, limits):
+    im = ax.imshow(Z, extent=extent, vmin=vlim[0], vmax=vlim[1])
+    cb = cax.colorbar(im)
+    cb.set_ticks((vlim[0], vlim[1]))
+# This affects all axes because we set share_all = True.
+grid.axes_llc.set_xticks([-2, 0, 2])
+grid.axes_llc.set_yticks([-2, 0, 2])
+
 
 plt.show()
