Merge pull request #2997 from dopplershift/simple-fronts-plot

DOC: Add simple example plotting fronts using path effects

examples/plots/Simple_Fronts_Plot.py

@@ -0,0 +1,35 @@
+# Copyright (c) 2023 MetPy Developers.
+# Distributed under the terms of the BSD 3-Clause License.
+# SPDX-License-Identifier: BSD-3-Clause
+"""
+=========================
+Simple Plotting of Fronts
+=========================
+This uses MetPy's path effects for matplotlib that can be used to represent a line as a
+traditional front. This example relies on already having location information for the
+boundaries you would like to plot.
+"""
+
+import matplotlib.pyplot as plt
+import numpy as np
+
+from metpy.plots import ColdFront, WarmFront
+
+###########################################
+# Define some synthetic points to represent the low pressure system and its frontal boundaries.
+low_lon, low_lat = -94, 32
+cold_lat = np.linspace(low_lat - 0.15, low_lat - 1.75, 100)
+cold_lon = (low_lon + 0.25) - (cold_lat - (low_lat - 0.5))**2
+
+warm_lon = np.linspace(low_lon + 0.3, low_lon + 5, 100)
+warm_lat = (low_lat + 0.3) - (warm_lon - (low_lon + 2))**2 / 12
+
+###########################################
+# Draw the low as an "L" using matplotlib's `text()` method, then plot the fronts as
+# standard lines, but add our path effects.
+fig, ax = plt.subplots(figsize=(8, 8), dpi=150)
+ax.text(low_lon, low_lat, 'L', color='red', size=30,
+        horizontalalignment='center', verticalalignment='center')
+ax.plot(cold_lon, cold_lat, 'blue', path_effects=[ColdFront(size=8, spacing=1.5)])
+ax.plot(warm_lon, warm_lat, 'red', path_effects=[WarmFront(size=8, spacing=1.5)])
+plt.show()