Merge pull request #6476 from afvincent/common_example_for_style_sheets

NelleV · NelleV · commit 992b5eef7873 · 2016-10-21T13:50:43.000-07:00
Add a common example to compare style sheets
diff --git a/examples/style_sheets/style_sheets_reference.py b/examples/style_sheets/style_sheets_reference.py
@@ -0,0 +1,146 @@
+"""
+======================
+Style sheets reference
+======================
+
+This script demonstrates the different available style sheets on a
+common set of example plots: scatter plot, image, bar graph, patches,
+line plot and histogram,
+
+"""
+
+import numpy as np
+import matplotlib.pyplot as plt
+
+
+def plot_scatter(ax, prng, nb_samples=100):
+    """Scatter plot.
+    """
+    for mu, sigma, marker in [(-.5, 0.75, 'o'), (0.75, 1., 's')]:
+        x, y = prng.normal(loc=mu, scale=sigma, size=(2, nb_samples))
+        ax.plot(x, y, ls='none', marker=marker)
+    ax.set_xlabel('X-label')
+    return ax
+
+
+def plot_colored_sinusoidal_lines(ax):
+    """Plot sinusoidal lines with colors following the style color cycle.
+    """
+    L = 2 * np.pi
+    x = np.linspace(0, L)
+    nb_colors = len(plt.rcParams['axes.prop_cycle'])
+    shift = np.linspace(0, L, nb_colors, endpoint=False)
+    for s in shift:
+        ax.plot(x, np.sin(x + s), '-')
+    ax.set_xlim([x[0], x[-1]])
+    return ax
+
+
+def plot_bar_graphs(ax, prng, min_value=5, max_value=25, nb_samples=5):
+    """Plot two bar graphs side by side, with letters as x-tick labels.
+    """
+    x = np.arange(nb_samples)
+    ya, yb = prng.randint(min_value, max_value, size=(2, nb_samples))
+    width = 0.25
+    ax.bar(x, ya, width)
+    ax.bar(x + width, yb, width, color='C2')
+    ax.set_xticks(x + width)
+    ax.set_xticklabels(['a', 'b', 'c', 'd', 'e'])
+    return ax
+
+
+def plot_colored_circles(ax, prng, nb_samples=15):
+    """Plot circle patches.
+
+    NB: draws a fixed amount of samples, rather than using the length of
+    the color cycle, because different styles may have different numbers
+    of colors.
+    """
+    for sty_dict, j in zip(plt.rcParams['axes.prop_cycle'], range(nb_samples)):
+        ax.add_patch(plt.Circle(prng.normal(scale=3, size=2),
+                                radius=1.0, color=sty_dict['color']))
+    # Force the limits to be the same across the styles (because different
+    # styles may have different numbers of available colors).
+    ax.set_xlim([-4, 8])
+    ax.set_ylim([-5, 6])
+    ax.set_aspect('equal', adjustable='box')  # to plot circles as circles
+    return ax
+
+
+def plot_image_and_patch(ax, prng, size=(20, 20)):
+    """Plot an image with random values and superimpose a circular patch.
+    """
+    values = prng.random_sample(size=size)
+    ax.imshow(values, interpolation='none')
+    c = plt.Circle((5, 5), radius=5, label='patch')
+    ax.add_patch(c)
+    # Remove ticks
+    ax.set_xticks([])
+    ax.set_yticks([])
+
+
+def plot_histograms(ax, prng, nb_samples=10000):
+    """Plot 4 histograms and a text annotation.
+    """
+    params = ((10, 10), (4, 12), (50, 12), (6, 55))
+    for a, b in params:
+        values = prng.beta(a, b, size=nb_samples)
+        ax.hist(values, histtype="stepfilled", bins=30, alpha=0.8, normed=True)
+    # Add a small annotation.
+    ax.annotate('Annotation', xy=(0.25, 4.25), xycoords='data',
+                xytext=(0.9, 0.9), textcoords='axes fraction',
+                va="top", ha="right",
+                bbox=dict(boxstyle="round", alpha=0.2),
+                arrowprops=dict(
+                          arrowstyle="->",
+                          connectionstyle="angle,angleA=-95,angleB=35,rad=10"),
+                )
+    return ax
+
+
+def plot_figure(style_label=""):
+    """Setup and plot the demonstration figure with a given style.
+    """
+    # Use a dedicated RandomState instance to draw the same "random" values
+    # across the different figures.
+    prng = np.random.RandomState(96917002)
+
+    # Tweak the figure size to be better suited for a row of numerous plots:
+    # double the width and halve the height. NB: use relative changes because
+    # some styles may have a figure size different from the default one.
+    (fig_width, fig_height) = plt.rcParams['figure.figsize']
+    fig_size = [fig_width * 2, fig_height / 2]
+
+    fig, axes = plt.subplots(ncols=6, nrows=1, num=style_label,
+                             figsize=fig_size, squeeze=True)
+    axes[0].set_ylabel(style_label)
+
+    plot_scatter(axes[0], prng)
+    plot_image_and_patch(axes[1], prng)
+    plot_bar_graphs(axes[2], prng)
+    plot_colored_circles(axes[3], prng)
+    plot_colored_sinusoidal_lines(axes[4])
+    plot_histograms(axes[5], prng)
+
+    fig.tight_layout()
+
+    return fig
+
+
+if __name__ == "__main__":
+
+    # Setup a list of all available styles, in alphabetical order but
+    # the `default` and `classic` ones, which will be forced resp. in
+    # first and second position.
+    style_list = list(plt.style.available)  # *new* list: avoids side effects.
+    style_list.remove('classic')  # `classic` is in the list: first remove it.
+    style_list.sort()
+    style_list.insert(0, u'default')
+    style_list.insert(1, u'classic')
+
+    # Plot a demonstration figure for every available style sheet.
+    for style_label in style_list:
+        with plt.style.context(style_label):
+            fig = plot_figure(style_label=style_label)
+
+    plt.show()
