<div dir="ltr"><br><div class="gmail_quote"><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
but why then does it work fine for me?<br>
I downloaded a 180W tile, that looks fine too:<br>
<a href="ftp://e0srp01u.ecs.nasa.gov/srtm/version2/SRTM3/Australia/S20W180.hgt.zip" target="_blank">ftp://e0srp01u.ecs.nasa.gov/srtm/version2/SRTM3/Australia/S20W180.hgt.zip</a><br>
....<br>
Origin = (-180.000416666666666,-18.999583333333334)<br>
<div class="Ih2E3d">Pixel Size = (0.000833333333333,-0.000833333333333)</div></blockquote><div class="Ih2E3d"><br>I grabbed the same tile and imported it into GRASS using r.in.srtm and am having the same issue:<br><br>> gdalinfo S20W180.hgt<br>
<br>Origin = (-180.000416666666666,-18.999583333333334)<br>Pixel Size = (0.000833333333333,-0.000833333333333)<br><br>> r.in.srtm input=S20W180 output=S20W180<br><br>> cat /location/mapset/cellhd/S20W180<br><br>proj: 3<br>
zone: 0<br>north: 18:59:58.5S<br>south: 20:00:01.5S<br>east: 178:59:58.5W<br>west: 179:59:58.5E<br>cols: 1201<br>rows: 1201<br>e-w resol: 0:00:03<br>n-s resol: 0:00:03<br>format: 3<br>
compressed: 1<br><br>> gdalinfo /location/mapset/cellhd/S20W180<br><br>Origin = (179.999583333333334,-18.999583333333334)<br>Pixel Size = (0.000833333333333,-0.000833333333333)<br><br>r.out.gdal outputs a GeoTiff consistent with this gdalinfo output - so shifted 180E.<br>
<br>
<br>
</div><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">where do your .tif files come from?</blockquote><div><br>I wrote a python script that creates these as equal divisions of an input area (in this case the world). I wanted to use them along with srtm, so I used the same res and pixel registration scheme. I looked into it a bit further and noticed that my script is using a truncated version of the res variable (initialized to 1/1200):<br>
<br>geotransform:<br>(-180.000416667, 0.00083333333333299999, 0.0, 10.0004166667, 0.0, -0.00083333333333299999)<br><br>cat cellhd/W180N10<br><br>proj: 3<br>zone: 0<br>north: 10:00:01.5N<br>south: 10:00:01.5S<br>
east: 159:59:58.500001W<br>west: 179:59:58.499999E<br>cols: 24001<br>rows: 24001<br>e-w resol: 0:00:03<br>n-s resol: 0:00:03<br>format: 0<br>compressed: 1<br><br>I fixed this and the precision issue went away. But as with the srtm tile, it doesn't fix the e-w region issue. <br>
</div></div><br></div>