Format docstring in cartesian_power.py

Author: willschlitzer

examples/projections/nongeo/cartesian_power.py

@@ -3,8 +3,8 @@
 ===============
 
 **x**\ *width*\ [**p**\ *p-value*]/[*height*\ [**p**\ *p-value*]]: Give the
-``width`` of the figure and the optional argument ``height``. The axis or axes with a
-logarithmic transformation requires ``"p"`` and the power transformation for that axis.
+*width* of the figure and the optional argument *height*. The axis or axes with a
+logarithmic transformation requires **p** and the power transformation for that axis.
 """
 import pygmt
 import numpy as np