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<p class="MsoNormal"><span lang="EN-US" style="mso-fareast-language:EN-US">Strange, I don’t see an HDF5 driver in my list of drivers but I do include it in the GDAL build.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="mso-fareast-language:EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="mso-fareast-language:EN-US">$ gdalinfo --formats | grep HDF<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="mso-fareast-language:EN-US"> HDF4 -raster,multidimensional raster- (ros): Hierarchical Data Format Release 4<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="mso-fareast-language:EN-US"> HDF4Image -raster- (rw+): HDF4 Dataset<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="mso-fareast-language:EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="mso-fareast-language:EN-US">Also<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="mso-fareast-language:EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="mso-fareast-language:EN-US">$ gdalinfo "NETCDF:"U.mat<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="mso-fareast-language:EN-US">ERROR 4: NETCDF:U.mat: No such file or directory<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="mso-fareast-language:EN-US">gdalinfo failed - unable to open 'NETCDF:U.mat'.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="mso-fareast-language:EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="mso-fareast-language:EN-US">I’m sending attached the U.mat file<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="mso-fareast-language:EN-US"><o:p> </o:p></span></p>
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<p class="MsoNormal"><b><span lang="EN-US">From:</span></b><span lang="EN-US"> Even Rouault <even.rouault@spatialys.com>
<br>
<b>Sent:</b> Monday, April 18, 2022 7:07 PM<br>
<b>To:</b> Joaquim Manuel Freire Luís <jluis@ualg.pt>; gdal-dev@lists.osgeo.org<br>
<b>Subject:</b> Re: [gdal-dev] -if netCDF fails to read Matlab .mat files<o:p></o:p></span></p>
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<p class="MsoNormal"><o:p> </o:p></p>
<p>Joaquim,<o:p></o:p></p>
<p><a href="https://www.loc.gov/preservation/digital/formats/fdd/fdd000440.shtml">https://www.loc.gov/preservation/digital/formats/fdd/fdd000440.shtml</a> mentions HDF5, but I don't know if it is HDF5-only or the HDF5 profile of netCDF 4.<o:p></o:p></p>
<p>From my tests trying to simulate the situation (I don't have a .mat file handy),<o:p></o:p></p>
<p>- if it is netCDF 3 file (non-HDF5), the netCDF driver should be able to open even with the .mat extension<o:p></o:p></p>
<p>- if it is netCDF 4 file, <o:p></o:p></p>
<p> - and the netCDF and HDF5 drivers are present, the HDF5 driver will kick in. The reason is that there's no easy way to recognize a HDF5 file from a netCDF 4 from their header, so the netCDF driver has a white list of extensions (which doesn't include
.mat) when it sees the HDF5 driver is there, since it knows it is a potential fallback<o:p></o:p></p>
<p> - and only the netCDF driver is present, it will kick in<o:p></o:p></p>
<p> - and only the HDF5 driver is present, it will kick in<o:p></o:p></p>
<p>So basically I don't reproduce your issue.<o:p></o:p></p>
<p>You should be able to force the NetCDF driver by prefixing "NETCDF:" to the filename (the -if flag only restricts drivers which are probed. it doesn't force a driver to accept a file)<o:p></o:p></p>
<p>Even<o:p></o:p></p>
<p><o:p> </o:p></p>
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<p class="MsoNormal">Le 18/04/2022 à 18:31, Joaquim Manuel Freire Luís a écrit :<o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span lang="EN-US">Hi,</span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span lang="EN-US"> </span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span lang="EN-US">Matlab creates files in what they call the “mat” format (with a .mat extension) but which in fact are files in netCDF/HDF
</span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span lang="EN-US"> </span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span lang="EN-US">And indeed we can read them … but only if renamed to .nc</span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span lang="EN-US"> </span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span lang="EN-US">Why is this failing?</span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span lang="EN-US"> </span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span lang="EN-US">$ gdalinfo -if netCDF windaa.mat</span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span lang="EN-US">ERROR 4: `windaa.mat' not recognized as a supported file format.</span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span lang="EN-US">gdalinfo failed - unable to open 'windaa.mat'.</span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span lang="EN-US"> </span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span lang="EN-US">But this works</span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span lang="EN-US"> </span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span lang="EN-US">$ gdalinfo windaa.nc</span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span lang="EN-US">Driver: netCDF/Network Common Data Format</span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span lang="EN-US">Files: windaa.nc</span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span lang="EN-US">Size is 512, 512</span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span lang="EN-US">Subdatasets:</span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span lang="EN-US"> SUBDATASET_1_NAME=NETCDF:"windaa.nc":u</span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span lang="EN-US"> SUBDATASET_1_DESC=[15x41x35] u (64-bit floating-point)</span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span lang="EN-US"> SUBDATASET_2_NAME=NETCDF:"windaa.nc":v</span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span lang="EN-US"> SUBDATASET_2_DESC=[15x41x35] v (64-bit floating-point)</span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span lang="EN-US">…</span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span lang="EN-US"> </span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span lang="EN-US"> </span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span lang="EN-US"> </span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span lang="EN-US">Joaquim</span><o:p></o:p></p>
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<p class="MsoNormal"><br>
<br>
<o:p></o:p></p>
<pre>_______________________________________________<o:p></o:p></pre>
<pre>gdal-dev mailing list<o:p></o:p></pre>
<pre><a href="mailto:gdal-dev@lists.osgeo.org">gdal-dev@lists.osgeo.org</a><o:p></o:p></pre>
<pre><a href="https://lists.osgeo.org/mailman/listinfo/gdal-dev">https://lists.osgeo.org/mailman/listinfo/gdal-dev</a><o:p></o:p></pre>
</blockquote>
<pre>-- <o:p></o:p></pre>
<pre><a href="http://www.spatialys.com">http://www.spatialys.com</a><o:p></o:p></pre>
<pre>My software is free, but my time generally not.<o:p></o:p></pre>
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