DOC: show the matplotlib widget backend

Author: mgeier

doc/code-cells.ipynb

@@ -419,6 +419,34 @@
     "fig"
    ]
   },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "Instead of the default `inline` plotting backend,\n",
+    "you can also use the `widget` backend\n",
+    "(which needs the `ipympl` package to be installed):"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "%matplotlib widget"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "fig, ax = plt.subplots(figsize=[6, 3])\n",
+    "ax.plot([4, 9, 7, 20, 6, 33, 13, 23, 16, 62, 8]);"
+   ]
+  },
   {
    "cell_type": "markdown",
    "metadata": {},

doc/requirements.txt

@@ -1,6 +1,7 @@
 ipykernel
 numpy
 matplotlib
+ipympl
 pandas
 # setuptools seems to be needed for pybtex, see
 # https://github.com/mcmtroffaes/sphinxcontrib-bibtex/issues/345: