.. _example_36:

(36) Spherical gridding using Renka's algorithms
------------------------------------------------

The next script produces the plot in Figure. Here
we demonstrate how :doc:`sphinterpolate </sphinterpolate>` can be used
to perform spherical gridding.  Our example uses early measurements of
the radius of Mars from Mariner 9 and Viking Orbiter spacecrafts.  The
middle panels shows the data distribution while the top and bottom panel
are images of the interpolation using a piecewise linear interpolation
and a smoothed spline interpolation, respectively.  For spherical gridding
with large volumes of data we recommend :doc:`sphinterpolate </sphinterpolate>`
while for small data sets (such as this one, actually) you have more flexibility
with :doc:`greenspline </greenspline>`.

.. literalinclude:: /_verbatim/example_36.txt
   :language: bash

.. figure:: /_images/example_36.*
   :width: 500 px
   :align: center

   Spherical gridding using Renka\'s algorithms.