matplotlib · NelleV · Jun 9, 2018 · Jun 9, 2018 · Jun 9, 2018 · ImportanceOfBeingErnest
diff --git a/examples/lines_bars_and_markers/timeline.py b/examples/lines_bars_and_markers/timeline.py
@@ -0,0 +1,69 @@
+"""
+===============================================
+Creating a timeline with lines, dates, and text
+===============================================
+
+How to create a simple timeline using Matplotlib release dates.
+
+Timelines can be created with a collection of dates and text. In this example,
+we show how to create a simple timeline using the dates for recent releases
+of Matplotlib. First, we'll pull the data from GitHub.
+"""
+
+import matplotlib.pyplot as plt
+import numpy as np
+import matplotlib.dates as mdates
+from datetime import datetime
+import urllib.request
+import json
+
+# Grab a list of Matplotlib releases
+url = 'https://api.github.com/repos/matplotlib/matplotlib/releases'
+data = json.loads(urllib.request.urlopen(url).read().decode())
+
+names = []
+dates = []
+for irelease in data:
+    if 'rc' not in irelease['tag_name'] and 'b' not in irelease['tag_name']:
+        names.append(irelease['tag_name'])
+        # Convert date strings (e.g. 2014-10-18T18:56:23Z) to datetime
+        dates.append(datetime.strptime(irelease['published_at'],
+                     "%Y-%m-%dT%H:%M:%SZ"))
+
+##############################################################################
+# Next, we'll iterate through each date and plot it on a horizontal line.
+# We'll add some styling to the text so that overlaps aren't as strong.
+#
+# Note that Matplotlib will automatically plot datetime inputs.
+
+levels = np.array([-5, 5, -3, 3, -1, 1])
+fig, ax = plt.subplots(figsize=(20, 5))
+
+# Create the base line
+start = min(dates)
+stop = max(dates)
+ax.plot((start, stop), (0, 0), 'k', alpha=.5)
+
+# Iterate through releases annotating each one
+for ii, (iname, idate) in enumerate(zip(names, dates)):
+    level = levels[ii % 6]
+    vert = 'top' if level < 0 else 'bottom'
+
+    ax.scatter(idate, 0, s=100, facecolor='w', edgecolor='k', zorder=9999)
+    # Plot a line up to the text
+    ax.plot((idate, idate), (0, level), c='r', alpha=.7)
+    # Give the text a faint background and align it properly
+    ax.text(idate, level, iname,
+            horizontalalignment='right', verticalalignment=vert, fontsize=14,
+            backgroundcolor=(1., 1., 1., .3))
+ax.set(title="Matplotlib release dates")
+# Set the xticks formatting
+# format xaxis with 3 month intervals
+ax.get_xaxis().set_major_locator(mdates.MonthLocator(interval=3))
+ax.get_xaxis().set_major_formatter(mdates.DateFormatter("%b %Y"))
+fig.autofmt_xdate()
+
+# Remove components for a cleaner look
+plt.setp((ax.get_yticklabels() + ax.get_yticklines() +
+          list(ax.spines.values())), visible=False)
+plt.show()