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<p>Javier,</p>
<p>The Conda vs your build difference can be easily explained
because Conda sets PROJ_NETWORK=ON in the conda environment.</p>
<p>When PROJ_NETWORK=ON, you can also get the expected result by
adding --bbox as well to cs2cs.<br>
</p>
<p>Now, the real issue is why PROJ_NETWORK=ON without --box does
(negatively) affect results .. ? The reason is that in that
situation the heuristics first finds the NKG related operations,
and does not think it needs to do extra efforts to consider
intermediate CRSs to get other solutions. Unfortunately the NKG
solutions only cover a small proportion of the area of use of the
source/target CRS, so they are not good general purpose solutions.</p>
<p>I've tuned this in <a class="moz-txt-link-freetext" href="https://github.com/OSGeo/PROJ/pull/4244">https://github.com/OSGeo/PROJ/pull/4244</a></p>
<p>Now:<br>
</p>
<p>$ echo 46 6 0 2024.6 | PROJ_NETWORK=OFF bin/cs2cs EPSG:9989
EPSG:4937 -d 9 <br>
45.999994986 5.999991132 -0.001870790 2024.6<br>
$ echo 46 6 0 2024.6 | PROJ_NETWORK=ON bin/cs2cs EPSG:9989
EPSG:4937 -d 9 <br>
45.999994986 5.999991132 -0.001870790 2024.6<br>
$ echo 46 6 0 2024.6 | PROJ_NETWORK=OFF bin/cs2cs EPSG:9989
EPSG:4937 -d 9 --bbox 5.5,45.5,6.5,46.5 <br>
45.999994986 5.999991132 -0.001870790 2024.6<br>
$ echo 46 6 0 2024.6 | PROJ_NETWORK=ON bin/cs2cs EPSG:9989
EPSG:4937 -d 9 --bbox 5.5,45.5,6.5,46.5 <br>
45.999994986 5.999991132 -0.001870790 2024.6<br>
<br>
</p>
<p>(Anybody wanting to do a "Fast, reliable and geodetic-grade
qualiy coordinate operation inference from a geodetic database"
master or PhD thesis ... ? I may consider mentoring them, unless
they decide to put some AI in the equation ;-) ;-). Or perhaps
that's actually the way to do it. Spy all conversations occurring
in offices of geodetic institutions and coordinate transformation
software editors, speech-to-text them, ingest that into a LLM, and
add some sanity filter on the garbage it spits out)</p>
<p>Even</p>
<span style="white-space: pre-wrap">
</span>
<pre class="moz-signature" cols="72">--
<a class="moz-txt-link-freetext" href="http://www.spatialys.com">http://www.spatialys.com</a>
My software is free, but my time generally not.</pre>
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