e Voigt filter. It is a measure for the noise amplitude.<p>

<dt> <b>width</b>
<dd>  the width of the gaussian or boxcar filters
</dl>

Filter the data by taking the transform, apply a particular filter
shape and the take the inverse transform. The ends of the original
data are first multiplied by a cosine bell of width <b>nrise</b>, to
bring it smoothly down to zero and hence avoid any end effects (see <a
href="mask.html"> mask</a>). A value of <b>nop/10</b> is usually
sufficient.<p>

The first form uses a