.. _example_07:

(7) A simple location map
-------------------------

Many scientific papers start out by showing a location map of the region
of interest. This map will typically also contain certain features and
labels. This example will present a location map for the equatorial
Atlantic ocean, where fracture zones and mid-ocean ridge segments have
been plotted. We also would like to plot earthquake locations and
available isochrons. We have obtained one file, ``quakes_07.txt``, which contains the
position and magnitude of available earthquakes in the region. We choose
to use magnitude/40 for the symbol-size in cm. The digital fracture
zone traces (``fz_07.txt``) and isochrons (0 isochron as ``ridge_07.txt``,
the rest as ``isochron_07.txt``) were
digitized from available maps [1]_. We create the final location map
with the following script:

.. literalinclude:: /_verbatim/ex07.txt
   :language: bash

Here a simple one-liner creates a simple legend in the upper-right corner.

.. figure:: /_images/ex07.*
   :width: 500 px
   :align: center

   A typical location map.

Footnote
~~~~~~~~

.. [1]
   These data are available on CD-ROM from NCEI (www.ncei.noaa.gov).
