Add an example for plotting multi-parameter symbols (#772)

Co-authored-by: Dongdong Tian <[email protected]>

Author: michaelgrund

examples/gallery/plot/multi-parameter-symbols.py

@@ -0,0 +1,63 @@
+"""
+Multi-parameter symbols
+-------------------------
+
+The :meth:`pygmt.Figure.plot` method can plot individual multi-parameter symbols by passing 
+the corresponding shortcuts listed below to the ``style`` option. Additionally, we must define 
+the required parameters in a 2d list or numpy array (``[[parameters]]`` for a single symbol 
+or ``[[parameters_1],[parameters_2],[parameters_i]]`` for several ones) or use an 
+appropriately formatted input file and pass it to ``data``. 
+
+The following symbols are available:
+
+- **e**: ellipse, ``[[lon, lat, direction, major_axis, minor_axis]]``
+- **j**: rotated rectangle, ``[[lon, lat, direction, width, height]]``
+- **r**: rectangle, ``[[lon, lat, width, height]]``
+- **R**: rounded rectangle, ``[[lon, lat, width, height, radius]]``
+- **w**: pie wedge, ``[[lon, lat, radius, startdir, stopdir]]``, the last two arguments are 
+  directions given in degrees counter-clockwise from horizontal 
+
+Upper-case versions **E**, **J**, and **W** are similar to **e**, **j** and **w** but expect geographic 
+azimuths and distances.
+
+For more advanced options, see the full option list at :gmt-docs:`plot.html`.
+"""
+
+import numpy as np
+import pygmt
+
+fig = pygmt.Figure()
+
+fig.basemap(region=[0, 6, 0, 2], projection="x3c", frame=True)
+
+###################
+# ELLIPSE
+data = np.array([[0.5, 1, 45, 3, 1]])
+
+fig.plot(data=data, style="e", color="orange", pen="2p,black")
+
+###################
+# ROTATED RECTANGLE
+data = np.array([[1.5, 1, 120, 5, 0.5]])
+
+fig.plot(data=data, style="j", color="red3", pen="2p,black")
+
+###################
+# RECTANGLE
+data = np.array([[3, 1, 4, 1.5]])
+
+fig.plot(data=data, style="r", color="dodgerblue", pen="2p,black")
+
+###################
+# ROUNDED RECTANGLE
+data = np.array([[4.5, 1, 1.25, 4, 0.5]])
+
+fig.plot(data=data, style="R", color="seagreen", pen="2p,black")
+
+###################
+# PIE WEDGE
+data = np.array([[5.5, 1, 2.5, 45, 330]])
+
+fig.plot(data=data, style="w", color="lightgray", pen="2p,black")
+
+fig.show()