it.sf_poly.sph_harm.h4"></a>
        <span class="phrase"><a name="math_toolkit.sf_poly.sph_harm.implementation"></a></span><a class="link" href="sph_harm.html#math_toolkit.sf_poly.sph_harm.implementation">Implementation</a>
      </h5>
<p>
        These functions are implemented fairly naively using the formulae given above.
        Some extra care is taken to prevent roundoff error when converting from polar
        coordinates (so for example the <span class="emphasis"><em>1-x<sup>2</sup></em></span> ter