Definitely first resample, then calculate derivatives - otherwise your results will be totally wrong. Depending on what kind of resampling you do, you could e.g. take a flat area and see it as slanted in a DEM with reduced resolution.<br clear="all">
<p style="margin-top:0px;margin-bottom:0px;margin-left:0px;margin-right:0px;text-indent:0px"><span style="font-family:arial,sans-serif;font-size:13px;background-color:rgb(255,255,255)"></span></p><p>--<br></p><p>B.Sc. Daniel Lee<br>
Geschäftsführung für Forschung und Entwicklung<br>ISIS - International Solar Information Solutions GbR<br>Vertreten durch: Daniel Lee, Nepomuk Reinhard und Nils Räder<br></p><p>Softwarecenter 3<br>35037 Marburg<br>Festnetz: <a value="+4964213796256" style="color:rgb(28,81,168)">+49 6421 379 6256</a><br>
Mobil: <a value="+4917661277269" style="color:rgb(28,81,168)">+49 176 6127 7269</a><br>E-Mail: <a href="mailto:Lee@isi-solutions.org" style="color:rgb(28,81,168)" target="_blank">Lee@isi-solutions.org</a><br>Web: <a href="http://www.isi-solutions.org/" style="color:rgb(28,81,168)" target="_blank">http://www.isi-solutions.org</a></p>
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<br><br><div class="gmail_quote">2012/6/3 Carlos Grohmann <span dir="ltr"><<a href="mailto:carlos.grohmann@gmail.com" target="_blank">carlos.grohmann@gmail.com</a>></span><br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
<div>
Hi all.
</div><div><br></div><div>The other day something popped on my mind, which I think could end in some research paper, but</div><div>before I venture into it I decided to ask you guys about it. I did some googling and got nothing.</div>
<div><br></div><div>So, considering a large area DEM: if I want its derivatives (slope, aspect, etc) in large-scale (larger than</div><div>the original DEM), which one is best, to resample the DEM and then calculate the derivatives, or to calculate</div>
<div>the derivatives and resample them? Much difference expected? The same?</div><div><br></div><div>best</div><span class="HOEnZb"><font color="#888888"><div><br></div><div>Carlos</div>
<div><div><br></div><div>-- </div><div><span style="text-indent:0px;letter-spacing:normal;font-variant:normal;text-align:-webkit-auto;font-style:normal;display:inline!important;font-weight:normal;float:none;line-height:normal;text-transform:none;font-size:small;white-space:normal;font-family:arial;word-spacing:0px">Prof. Carlos Henrique Grohmann</span><br style="text-indent:0px;letter-spacing:normal;font-variant:normal;text-align:-webkit-auto;font-style:normal;font-weight:normal;line-height:normal;text-transform:none;font-size:small;white-space:normal;font-family:arial;word-spacing:0px">
<span style="text-indent:0px;letter-spacing:normal;font-variant:normal;text-align:-webkit-auto;font-style:normal;display:inline!important;font-weight:normal;float:none;line-height:normal;text-transform:none;font-size:small;white-space:normal;font-family:arial;word-spacing:0px">Institute of Geosciences - Univ. of São Paulo, Brazil</span><div style="text-indent:0px;letter-spacing:normal;font-variant:normal;text-align:-webkit-auto;font-style:normal;font-weight:normal;line-height:normal;text-transform:none;font-size:small;white-space:normal;font-family:arial;word-spacing:0px">
- Digital Terrain Analysis | GIS | Remote Sensing - </div><div style="text-indent:0px;letter-spacing:normal;font-variant:normal;text-align:-webkit-auto;font-style:normal;font-weight:normal;line-height:normal;text-transform:none;font-size:small;white-space:normal;font-family:arial;word-spacing:0px">
<br><a href="http://carlosgrohmann.com/" target="_blank">http://carlosgrohmann.com</a><div>________________<br>Can’t stop the signal.</div></div></div><div>Sent with <a href="http://www.sparrowmailapp.com/?sig" target="_blank">Sparrow</a></div>
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