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<p class="MsoNormal"><span lang="EN-US">Hi,<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">I am trying to read some floating point data from a VRT file. The VRT file references a set of VRT files which again references a set of GeoTIFF files.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Using Python I call dataset.ReadAsArray(x, y, width, height) to request the data. In my case I end up requesting data which is outside the bounds of the VRT file resulting in the following error:<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span lang="EN-US" style="font-size:10.0pt;font-family:Consolas;color:red">ERROR 5: my.vrt, band 1: Access window out of range in RasterIO(). Requested</span><span lang="EN-US" style="font-size:10.0pt;font-family:Consolas"><o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:10.0pt;font-family:Consolas;color:red">(1129975,637475) of size 2550x2550 on raster of 1132500x885000.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:10.0pt;font-family:Consolas;color:red"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">If I was working with a normal GeoTIFF file I could calculate if I was outside the bounds and crop my request accordingly. But since I am working with a VRT file I don’t know how to determine if the VRT file has coverage
or not. I vaguely remember a similar issue with gdal_translate which was fixed to allow requesting data partially and completely outside the bounds of the VRT file and just return zero (?) on the cells outside.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Shouldn’t this also occur in my case described above even though I am using python and not gdal_translate to request data?<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">I am using python 2.7.6 and GDAL 2.1.3 x64 from OSGeo4W.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Regards, Casper<o:p></o:p></span></p>
<p class="MsoNormal"><o:p> </o:p></p>
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