<div dir="ltr">Thank you Markus.<br><br>That makes sense for me, I have horizontal distances between points of around 1-2 km, and vertical distances range between 10-20 m. Further trials with "v.vol.rst -c" showed better results for zmult=50-100, getting worse both for higher and lower values of zmult.<br>
<br>Regards <br><br>Eduardo<br><br><div class="gmail_quote">2008/10/6 Markus Neteler <span dir="ltr"><<a href="mailto:neteler@osgeo.org">neteler@osgeo.org</a>></span><br><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
<div><div></div><div class="Wj3C7c">On Fri, Oct 3, 2008 at 9:27 AM, Eduardo corbelle<br>
<<a href="mailto:eduardo.corbelle@gmail.com">eduardo.corbelle@gmail.com</a>> wrote:<br>
> Hello list:<br>
><br>
> I've been working recently with v.vol.rst and I have doubts about<br>
> the real function of the parameter "zmult": the manual says it allows<br>
> the user to re-scale (change units of) the z coordinates of the data; but<br>
> I obtain better results when using high values (about 20) of zmult even if<br>
> no unit transformation (re-scaling) is needed at all (all data in metres). Could<br>
> anyone give me a<br>
> hint on the actual role of zmult in the interpolation process? Is it<br>
> reasonable to use "very" high values (e.g. 100)?<br>
<br>
</div></div>Helena once told me:<br>
<br>
Rescaling of z-coordinates is for example needed when the distances in<br>
vertical direction are much smaller than the horizontal distances, if<br>
that is the case, the value of zmult should be selected so that the<br>
vertical and horizontal distances have about the same magnitude.<br>
<br>
Might this help as explanation?<br>
<font color="#888888"><br>
Markus<br>
</font></blockquote></div><br></div>