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<p class="MsoNormal">Hi all,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I’m seeing some odd contour line points being generated from gdal_contour and I was wondering whether anything else might have seen something similar?<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Using <i>gdal_contour –i 15.24 –a height e100n00.dt2 n00.shp</i> on the attached tile<span style="color:#1F497D"> (Removed as too large)</span> gives some contours which have points very close together. Take a look at the first three points
in the contour line below, there are all < 0.1m of each other which, given the height posts are spaced at 30m’s, seems very odd.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><b>Contour Line (381m):<o:p></o:p></b></p>
<p class="MsoNormal">(100.1727777777963, 0.5436111111111112)<o:p></o:p></p>
<p class="MsoNormal">(100.17277777777778, 0.5436111111039885)<o:p></o:p></p>
<p class="MsoNormal">(100.17277777770833, 0.5436111111111112)<o:p></o:p></p>
<p class="MsoNormal">(100.1725, 0.5437345679012346)<o:p></o:p></p>
<p class="MsoNormal">(100.17222222222223, 0.5438518518518518)<o:p></o:p></p>
<p class="MsoNormal">(100.1720833332639, 0.5438888888888889)<o:p></o:p></p>
<p class="MsoNormal">(100.17222222222223, 0.5440277778472222)<o:p></o:p></p>
<p class="MsoNormal">(100.1724074074074, 0.5441666666666667)<o:p></o:p></p>
<p class="MsoNormal">(100.1725, 0.5442222222222222)<o:p></o:p></p>
<p class="MsoNormal">(100.17277777777778, 0.5443888888888889)<o:p></o:p></p>
<p class="MsoNormal">(100.17305555555556, 0.5442592592592592)<o:p></o:p></p>
<p class="MsoNormal">(100.17314814814816, 0.5441666666666667)<o:p></o:p></p>
<p class="MsoNormal">(100.1731944445139, 0.5438888888888889)<o:p></o:p></p>
<p class="MsoNormal">(100.17305555555556, 0.5438562091503267)<o:p></o:p></p>
<p class="MsoNormal">(100.1727777777963, 0.5436111111111112)<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><b>Related DTED height posts (m):<o:p></o:p></b></p>
<p class="MsoNormal"> [371, 374, 377, 380, 379, 379]<o:p></o:p></p>
<p class="MsoNormal"> [376, 379, 382, 385, 382, 379]<o:p></o:p></p>
<p class="MsoNormal"> [379, 383, 386, 390, 383, 379]<o:p></o:p></p>
<p class="MsoNormal"> [368, 368, 377, 381, 366, 375]<o:p></o:p></p>
<p class="MsoNormal"> [364, 357, 347, 342, 329, 345] <o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Has anyone seen this before or know what is going on? For the majority of other contours the contour points are at least 30m apart.
<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Kind regards,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Owen<span style="color:black;mso-fareast-language:EN-GB"><o:p></o:p></span></p>
<p class="MsoNormal"><o:p> </o:p></p>
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