.. _example_08:

(8) A 3-D histogram
-------------------

The program :doc:`plot3d </plot3d>` allows us to plot
three-dimensional symbols, including columnar plots. As a simple
demonstration, we will convert a gridded netCDF of bathymetry into an
ASCII *xyz* table and use the height information to draw a 2-D
histogram in a 3-D perspective view. We also use the height information
to set to color of each column via a CPT file.  Our gridded bathymetry file is 
the 5 arc-minute global relief. Depth ranges
from -5000 meter to sea-level. We produce the Figure by running this script:

.. literalinclude:: /_verbatim/ex08.txt
   :language: bash

.. figure:: /_images/ex08.*
   :width: 500 px
   :align: center

   A 3-D histogram.