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Author: yvonnefroehlich

examples/gallery/lines/curves_area.py

@@ -23,16 +23,20 @@
 
 
 # %%
-# Fill the area between the two curves using the ``fill_between`` parameter.
+# Fill the areas between the two curves using the ``fill_between`` parameter.
+# Use the ``fill`` parameter and the modifier **+g** for ``fill_between`` to
+# set different fills for areas with y1 > y2 and y2 < y1, respectively. Use
+# the ``label`` parameter and the modifier **+l** for ``fill_between`` to
+# set the corresponding legend entries.
 
 fig = gmt.Figure()
 fig.basemap(region=[-10, 10, -5, 5], projection="X15c/5c", frame=True)
 
 fig.plot(
     data=data_df,
     fill="orange",
-    fill_between="c+gsteelblue+lshort < long",
     label="short > long",
+    fill_between="c+gsteelblue+lshort < long",
 )
 
 fig.legend()
@@ -41,9 +45,10 @@
 
 
 # %%
-# Additionally we can draw the curves.
+# Additionally to filling the areas, we can draw the curves. Use the ``pen``
+# parameter and the modifier **+p** for ``fill_between`` to set different
+# lines for the two curves y1 and y2, respectively.
 
-# Set up new Figure instance
 fig = gmt.Figure()
 fig.basemap(region=[-10, 10, -5, 5], projection="X15c/5c", frame=True)
 
@@ -58,16 +63,17 @@
 
 
 # %%
-# Compare to a horizontal line.
+# To compare a curve y1 to a horizontal line, append **+y** to ``fill_between``
+# and give the desired y-level.
 
-# Set up new Figure instance
 fig = gmt.Figure()
 fig.basemap(region=[-10, 10, -5, 5], projection="X15c/5c", frame=True)
 
 fig.plot(
     data=data_df[["x", "y1"]],
     fill="p8",
     pen="1p,black,solid",
+    # Define a horizontal line at y=0.42
     fill_between="c+gp17+p1p,black,dashed+y0.42",
 )