From b0a4959d93021c9073a85991802c655d8a4eee4f Mon Sep 17 00:00:00 2001 From: Tim Hoffmann <2836374+timhoffm@users.noreply.github.com> Date: Sun, 20 Oct 2019 20:06:50 +0200 Subject: [PATCH] Improve example for tick formatters --- examples/ticks_and_spines/tick-formatters.py | 101 +++++++------------ 1 file changed, 36 insertions(+), 65 deletions(-) diff --git a/examples/ticks_and_spines/tick-formatters.py b/examples/ticks_and_spines/tick-formatters.py index a5ce0927ffe6..000c2f6b74cc 100644 --- a/examples/ticks_and_spines/tick-formatters.py +++ b/examples/ticks_and_spines/tick-formatters.py @@ -3,52 +3,51 @@ Tick formatters =============== -Show the different tick formatters. +Tick formatters define how the numeric value associated with a tick on an axis +is formatted as a string. + +This example illustrates the usage and effect of the most common formatters. """ -import numpy as np import matplotlib.pyplot as plt import matplotlib.ticker as ticker -# Setup a plot such that only the bottom spine is shown -def setup(ax): +def setup(ax, title): + """Set up common parameters for the Axes in the example.""" + # only show the bottom spine + ax.yaxis.set_major_locator(ticker.NullLocator()) ax.spines['right'].set_color('none') ax.spines['left'].set_color('none') - ax.yaxis.set_major_locator(ticker.NullLocator()) ax.spines['top'].set_color('none') + + # define tick positions + ax.xaxis.set_major_locator(ticker.MultipleLocator(1.00)) + ax.xaxis.set_minor_locator(ticker.MultipleLocator(0.25)) + ax.xaxis.set_ticks_position('bottom') ax.tick_params(which='major', width=1.00, length=5) ax.tick_params(which='minor', width=0.75, length=2.5, labelsize=10) ax.set_xlim(0, 5) ax.set_ylim(0, 1) - ax.patch.set_alpha(0.0) + ax.text(0.0, 0.2, title, transform=ax.transAxes, + fontsize=14, fontname='Monospace', color='tab:blue') -fig = plt.figure(figsize=(8, 6)) -n = 7 +fig, axs = plt.subplots(7, 1, figsize=(8, 6)) # Null formatter -ax = fig.add_subplot(n, 1, 1) -setup(ax) -ax.xaxis.set_major_locator(ticker.MultipleLocator(1.00)) -ax.xaxis.set_minor_locator(ticker.MultipleLocator(0.25)) -ax.xaxis.set_major_formatter(ticker.NullFormatter()) -ax.xaxis.set_minor_formatter(ticker.NullFormatter()) -ax.text(0.0, 0.1, "NullFormatter()", fontsize=16, transform=ax.transAxes) +setup(axs[0], title="NullFormatter()") +axs[0].xaxis.set_major_formatter(ticker.NullFormatter()) # Fixed formatter -ax = fig.add_subplot(n, 1, 2) -setup(ax) -ax.xaxis.set_major_locator(ticker.MultipleLocator(1.0)) -ax.xaxis.set_minor_locator(ticker.MultipleLocator(0.25)) -majors = ["", "0", "1", "2", "3", "4", "5"] -ax.xaxis.set_major_formatter(ticker.FixedFormatter(majors)) -minors = [""] + ["%.2f" % (x-int(x)) if (x-int(x)) - else "" for x in np.arange(0, 5, 0.25)] -ax.xaxis.set_minor_formatter(ticker.FixedFormatter(minors)) -ax.text(0.0, 0.1, "FixedFormatter(['', '0', '1', ...])", - fontsize=15, transform=ax.transAxes) +setup(axs[1], title="FixedFormatter(['A', 'B', 'C', ...])") +# FixedFormatter should only be used together with FixedLocator. +# Otherwise, one cannot be sure where the labels will end up. +positions = [0, 1, 2, 3, 4, 5] +labels = ['A', 'B', 'C', 'D', 'E', 'F'] +axs[1].xaxis.set_major_locator(ticker.FixedLocator(positions)) +axs[1].xaxis.set_major_formatter(ticker.FixedFormatter(labels)) # FuncFormatter can be used as a decorator @@ -57,52 +56,24 @@ def major_formatter(x, pos): return "[%.2f]" % x -ax = fig.add_subplot(n, 1, 3) -setup(ax) -ax.xaxis.set_major_locator(ticker.MultipleLocator(1.00)) -ax.xaxis.set_minor_locator(ticker.MultipleLocator(0.25)) -ax.xaxis.set_major_formatter(major_formatter) -ax.text(0.0, 0.1, 'FuncFormatter(lambda x, pos: "[%.2f]" % x)', - fontsize=15, transform=ax.transAxes) - +setup(axs[2], title='FuncFormatter(lambda x, pos: "[%.2f]" % x)') +axs[2].xaxis.set_major_formatter(major_formatter) # FormatStr formatter -ax = fig.add_subplot(n, 1, 4) -setup(ax) -ax.xaxis.set_major_locator(ticker.MultipleLocator(1.00)) -ax.xaxis.set_minor_locator(ticker.MultipleLocator(0.25)) -ax.xaxis.set_major_formatter(ticker.FormatStrFormatter(">%d<")) -ax.text(0.0, 0.1, "FormatStrFormatter('>%d<')", - fontsize=15, transform=ax.transAxes) +setup(axs[3], title="FormatStrFormatter('#%d')") +axs[3].xaxis.set_major_formatter(ticker.FormatStrFormatter("#%d")) # Scalar formatter -ax = fig.add_subplot(n, 1, 5) -setup(ax) -ax.xaxis.set_major_locator(ticker.AutoLocator()) -ax.xaxis.set_minor_locator(ticker.AutoMinorLocator()) -ax.xaxis.set_major_formatter(ticker.ScalarFormatter(useMathText=True)) -ax.text(0.0, 0.1, "ScalarFormatter()", fontsize=15, transform=ax.transAxes) +setup(axs[4], title="ScalarFormatter()") +axs[4].xaxis.set_major_formatter(ticker.ScalarFormatter(useMathText=True)) # StrMethod formatter -ax = fig.add_subplot(n, 1, 6) -setup(ax) -ax.xaxis.set_major_locator(ticker.MultipleLocator(1.00)) -ax.xaxis.set_minor_locator(ticker.MultipleLocator(0.25)) -ax.xaxis.set_major_formatter(ticker.StrMethodFormatter("{x}")) -ax.text(0.0, 0.1, "StrMethodFormatter('{x}')", - fontsize=15, transform=ax.transAxes) +setup(axs[5], title="StrMethodFormatter('{x:.3f}')") +axs[5].xaxis.set_major_formatter(ticker.StrMethodFormatter("{x:.3f}")) # Percent formatter -ax = fig.add_subplot(n, 1, 7) -setup(ax) -ax.xaxis.set_major_locator(ticker.MultipleLocator(1.00)) -ax.xaxis.set_minor_locator(ticker.MultipleLocator(0.25)) -ax.xaxis.set_major_formatter(ticker.PercentFormatter(xmax=5)) -ax.text(0.0, 0.1, "PercentFormatter(xmax=5)", - fontsize=15, transform=ax.transAxes) - -# Push the top of the top axes outside the figure because we only show the -# bottom spine. -fig.subplots_adjust(left=0.05, right=0.95, bottom=0.05, top=1.05) +setup(axs[6], title="PercentFormatter(xmax=5)") +axs[6].xaxis.set_major_formatter(ticker.PercentFormatter(xmax=5)) +plt.tight_layout() plt.show()