Note
Click here to download the full example code
Frames, ticks, titles, and labels
Setting the style of the map frames, ticks, etc, is handled by the frame
parameter that all plotting methods of pygmt.Figure
.
import pygmt
Plot frame
By default, PyGMT does not add a frame to your plot. For example, we can plot the coastlines of the world with a Mercator projection:
fig = pygmt.Figure()
fig.coast(shorelines="1/0.5p", region=[-180, 180, -60, 60], projection="M25c")
fig.show()
![frames](../_images/sphx_glr_frames_001.png)
Out:
<IPython.core.display.Image object>
To add the default GMT frame to the plot, use frame="f"
in
pygmt.Figure.basemap
or any other plotting module:
fig = pygmt.Figure()
fig.coast(shorelines="1/0.5p", region=[-180, 180, -60, 60], projection="M25c")
fig.basemap(frame="f")
fig.show()
![frames](../_images/sphx_glr_frames_002.png)
Out:
<IPython.core.display.Image object>
Ticks and grid lines
The automatic frame (frame=True
or frame="a"
) sets the default GMT
style frame and automatically determines tick labels from the plot region.
fig = pygmt.Figure()
fig.coast(shorelines="1/0.5p", region=[-180, 180, -60, 60], projection="M25c")
fig.basemap(frame="a")
fig.show()
![frames](../_images/sphx_glr_frames_003.png)
Out:
<IPython.core.display.Image object>
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="M25c")
fig.basemap(frame="ag")
fig.show()
![frames](../_images/sphx_glr_frames_004.png)
Out:
<IPython.core.display.Image object>
Title
The figure title can be set by passing +ttitle to the frame
parameter of 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()
![frames](../_images/sphx_glr_frames_005.png)
Out:
<IPython.core.display.Image object>
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
parameter 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()
![frames](../_images/sphx_glr_frames_006.png)
Out:
<IPython.core.display.Image object>
Axis labels
Axis labels can be set by passing x+llabel (or starting with y if
labeling the y-axis) to the frame
parameter of
pygmt.Figure.basemap
. By default, all 4 map boundaries (or plot axes)
are plotted with both tick marks and axis labels. The axes are named as
W (west/left), S (south/bottom), N (north/top), and
E (east/right) sides of a figure. If an upper-case axis name is passed,
the axis is plotted with tick marks and axis labels. A lower case axis name
plots only the axis and tick marks.
The example below uses 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",
# Plot axis, tick marks, and axis labels on the west/left and south/bottom
# axes
# Plot axis and tick marks on the north/top and east/right axes
frame=["WSne", "xaf+lx-axis", "yaf+ly-axis"],
)
fig.show()
![frames](../_images/sphx_glr_frames_007.png)
Out:
<IPython.core.display.Image object>
Total running time of the script: ( 0 minutes 11.750 seconds)