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<p class=MsoNormal><span style='font-size:11.0pt;font-family:"OCR A Extended";
color:#1F497D'>I must have been doing something like that. I got frustrated
and started from scratch and am now getting the correct results.<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"OCR A Extended";
color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"OCR A Extended";
color:#1F497D'>Thank you guys help immensely. GDAL is great but the learning
curve is a bit steep at times.<o:p></o:p></span></p>
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color:#1F497D'><o:p> </o:p></span></p>
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<p class=MsoNormal><b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>From:</span></b><span
style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>
gdal-dev-bounces@lists.osgeo.org [mailto:gdal-dev-bounces@lists.osgeo.org] <b>On
Behalf Of </b>Belaid MOA<br>
<b>Sent:</b> Friday, July 31, 2009 4:04 PM<br>
<b>To:</b> gdal-dev@lists.osgeo.org<br>
<b>Subject:</b> RE: [gdal-dev] Help understanding GDALApplyGeoTransform
andGDALInvGeoTransform<o:p></o:p></span></p>
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<p class=MsoNormal style='margin-bottom:12.0pt'><span style='font-size:10.0pt;
font-family:"Verdana","sans-serif"'>Just out of curiosity, I ran your code on
my machine and I got exactly the same results as Even.<br>
I do not think that Endianity will cause such wrong results. Are you sure you
are not changing the values<br>
of new_x and new_y before printing them out?<br>
<br>
~Belaid.<br>
<br>
> From: even.rouault@mines-paris.org<br>
> To: gdal-dev@lists.osgeo.org<br>
> Subject: Re: [gdal-dev] Help understanding GDALApplyGeoTransform and
GDALInvGeoTransform<br>
> Date: Fri, 31 Jul 2009 20:20:46 +0200<br>
> CC: BCassanova@weather.com<br>
> <br>
> Bill,<br>
> <br>
> that's weird. Your code looks correct and I've just compiled it and I get
the <br>
> following results :<br>
> <br>
> lat-lon -127, 51<br>
> 7.24754e-13, 4.12115e-13<br>
> <br>
> The new_x, new_y values are almost 0 as expected (the small difference is
due <br>
> to numerical imprecision when computing the inverse geotransform).<br>
> <br>
> I can't understand why you get such wrong values.<br>
> <br>
> Le Friday 31 July 2009 19:56:39 Cassanova, Bill, vous avez écrit :<br>
> > double adfGeoTransform[6] = { -127, .011571482, 0, 51, 0, -.008993 };<br>
> ><br>
> > double adfReverseGeoTransform[6] = { 0, 0, 0, 0, 0, 0 };<br>
> ><br>
> > GDALInvGeoTransform( adfGeoTransform, adfReverseGeoTransform );<br>
> ><br>
> > double dfPixel = 0;<br>
> > double dfLine = 0;<br>
> > double x;<br>
> > double y;<br>
> ><br>
> > GDALApplyGeoTransform( adfGeoTransform, dfPixel, dfLine,
&x, &y );<br>
> ><br>
> > std::cout << "lat-lon " << x << ",
" << y << std::endl;<br>
> ><br>
> > double new_x;<br>
> > double new_y;<br>
> ><br>
> > GDALApplyGeoTransform( adfReverseGeoTransform, x, y,
&new_x, &new_y );<br>
> ><br>
> > std::cout << new_x << ", " << new_y
<< std::endl;<br>
> <br>
> <br>
> _______________________________________________<br>
> gdal-dev mailing list<br>
> gdal-dev@lists.osgeo.org<br>
> http://lists.osgeo.org/mailman/listinfo/gdal-dev<o:p></o:p></span></p>
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