Add description of hist

_episodes/03-plotting.md

@@ -556,6 +556,14 @@ Given `plot(X, Y)` it then takes a pair of coordinates from both variables as wi
 
 ### Histograms
 
+Another very common type of plot is the `histogram` which can be produced using
+the [`plt.hist()` function][matplotlib-hist].
+
+A `histogram` is a bar-plot where one axis represents the range of values in the data being plotted,
+and the other axis, a count of the values in the interval defined by the bar.
+The width of the bars is determined by the `bins` attribute which specifies
+how many bars should be displayed.
+
 ~~~
 import numpy as np
 import matplotlib.pyplot as plt
@@ -570,10 +578,10 @@ normal_dist = np.random.normal(mean, stdev, samples)
 
 # Create a histogram with the sampled values
 plt.hist(normal_dist, bins)
+
 # Add a dotted thin line grid on both axis
 plt.grid(linestyle="dotted", linewidth=1)
 plt.title(f"Normal distribution - mean={mean}, stdev={stdev}, samples={samples}, binning={1/bins}")
-plt.title(f"$X \\sim \\mathcal{N}(\\mu,\\,\\sigma^{2})$ - $\\mu$={mean}, $\\sigma^{2}$={stdev}, samples={samples}, binning={1/bins}")
 ~~~
 {: .language-python }
 

_includes/links.md

@@ -94,6 +94,7 @@
 [matplotlib-home]: https://matplotlib.org/
 [matplotlib-linestyle]: https://matplotlib.org/3.2.2/gallery/lines_bars_and_markers/linestyles.html
 [matplotlib-markerstyle]: https://matplotlib.org/3.2.2/api/markers_api.html
+[matplotlib-hist]: https://matplotlib.org/3.2.2/api/_as_gen/matplotlib.pyplot.hist.html
 [matplotlib-plot]: https://matplotlib.org/3.2.2/api/_as_gen/matplotlib.pyplot.plot.html
 [matplotlib-scatter]: https://matplotlib.org/3.2.2/api/_as_gen/matplotlib.pyplot.scatter.html
 [matplotlib-scatter-examples]: https://matplotlib.org/3.2.2/api/_as_gen/matplotlib.pyplot.scatter.html#examples-using-matplotlib-pyplot-scatter