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List, </div>
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I have a set of body-centered body-fixed coordinates that were computed with an ellipsoid of +a=3396190 +b=3376200. I am attempting to reproject these into a spherical datum (+R=3396190) using the pipeline syntax. For example, </div>
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+proj=pipeline +units=m</div>
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+step +proj=cart +a=3396190 +b=3376200</div>
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+step +proj=cart +R=3396190 </div>
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Which is failing with a unit warning. I suspect I am missing something basic.</div>
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I have looked at the geodesic -> Helmert -> geodesic transformation tutorial, but I am clearly misunderstanding something (<a href="https://proj.org/en/9.3/tutorials/EUREF2019/exercises/pipelines.html#geodetic-helmert-geodetic" id="LPlnk336899">https://proj.org/en/9.3/tutorials/EUREF2019/exercises/pipelines.html#geodetic-helmert-geodetic</a>)</div>
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Looking at these docs, I tried:</div>
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+proj=pipeline</div>
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+step +proj=cart +a=3396190 +b=3376200</div>
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+step +proj=helmert +z=19990 +convention=position_vector</div>
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+step +inv +proj=cart +R=3396190</div>
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But I get an invalid latitude error (which I believe means I am misspecifying the input system).</div>
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Any suggestions appreciated, </div>
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Jay</div>
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