Add tutorial for adding a map title (#720)

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

Author: 3 people

examples/tutorials/frames.py

@@ -16,15 +16,15 @@
 # coastlines of the world with a Mercator projection:
 
 fig = pygmt.Figure()
-fig.coast(shorelines="1/0.5p", region=[-180, 180, -60, 60], projection="M10i")
+fig.coast(shorelines="1/0.5p", region=[-180, 180, -60, 60], projection="M25c")
 fig.show()
 
 ########################################################################################
 # To add the default GMT frame to the plot, use ``frame="f"`` in
 # :meth:`pygmt.Figure.basemap` or any other plotting module:
 
 fig = pygmt.Figure()
-fig.coast(shorelines="1/0.5p", region=[-180, 180, -60, 60], projection="M10i")
+fig.coast(shorelines="1/0.5p", region=[-180, 180, -60, 60], projection="M25c")
 fig.basemap(frame="f")
 fig.show()
 
@@ -36,14 +36,63 @@
 # and automatically determines tick labels from the plot region.
 
 fig = pygmt.Figure()
-fig.coast(shorelines="1/0.5p", region=[-180, 180, -60, 60], projection="M10i")
+fig.coast(shorelines="1/0.5p", region=[-180, 180, -60, 60], projection="M25c")
 fig.basemap(frame="a")
 fig.show()
 
 ########################################################################################
 # Add automatic grid lines to the plot by adding a ``g`` to ``frame``:
 
 fig = pygmt.Figure()
-fig.coast(shorelines="1/0.5p", region=[-180, 180, -60, 60], projection="M10i")
+fig.coast(shorelines="1/0.5p", region=[-180, 180, -60, 60], projection="M25c")
 fig.basemap(frame="ag")
 fig.show()
+
+########################################################################################
+# Title
+# -----
+#
+# The figure title can be set by passing **+t**\ *title* to the ``frame`` parameter of
+# :meth:`pygmt.Figure.basemap`. Passing multiple arguments to ``frame`` can be done by
+# using a list, as show in the example below.
+
+fig = pygmt.Figure()
+# region="IS" specifies Iceland using the ISO country code
+fig.coast(shorelines="1/0.5p", region="IS", projection="M25c")
+fig.basemap(frame=["a", "+tIceland"])
+fig.show()
+
+########################################################################################
+# To use a title with multiple words, the title must be placed inside another set of
+# quotation marks. To prevent the quotation marks from appearing in the figure title,
+# the frame argument can be passed in single quotation marks and the title can be
+# passed in double quotation marks.
+
+fig = pygmt.Figure()
+# region="TT" specifies Trinidad and Tobago
+fig.coast(shorelines="1/0.5p", region="TT", projection="M25c")
+fig.basemap(frame=["a", '+t"Trinidad and Tobago"'])
+fig.show()
+
+########################################################################################
+# Axis labels
+# -----------
+#
+# Axis labels can be set by passing **x+l**\ *label* (or starting with y if
+# labeling the y-axis) if  to the ``frame`` parameter of :meth:`pygmt.Figure.basemap`.
+# Axis labels will be displayed on all primary axes, which the default is all sides of
+# the figure. To designate only some of the axes as primary, an argument that
+# capitlizes only the primary axes can be passed, which is ``"WSne"`` in the example
+# below. The letters correspond with west (left), south (bottom), north (top), and
+# east (right) sides of a figure.
+#
+# The example below used a Cartesian projection, as GMT does not allow axis labels to
+# be set for geographic maps.
+
+fig = pygmt.Figure()
+fig.basemap(
+    region=[0, 10, 0, 20],
+    projection="X10c/8c",
+    frame=["WSne", "x+lx-axis", "y+ly-axis"],
+)
+fig.show()