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<p class="MsoNormal">Hello PROJ9 Community,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I have 2 questions about transformations. First of all, I do not know one hundred percent about transformations.<o:p></o:p></p>
<p class="MsoNormal">I use a library I built myself for all possible Android platforms.<o:p></o:p></p>
<p class="MsoNormal">Now I am testing the library a little and have encountered the following problems:<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">1.<o:p></o:p></p>
<p class="MsoNormal">I get a list of all CRS (PJ_TYPE_CRS) with proj_get_crs_info_list_from_database(...).<o:p></o:p></p>
<p class="MsoNormal">For testing purposes, I then create a projection with all CRSs using proj_create_crs_to_crs(...), which I then normalize with
<o:p></o:p></p>
<p class="MsoNormal">proj_normalize_for_visualization(...).<o:p></o:p></p>
<p class="MsoNormal">My source is always WGS84 (EPSG:4326).<o:p></o:p></p>
<p class="MsoNormal">With some projections I get the error "No inverse operation" (PROJ_ERR_OTHER_NO_INVERSE_OP) after calling proj_get_crs_info_list_from_database.<o:p></o:p></p>
<p class="MsoNormal">What does this mean? Can I somehow create this projection differently?<o:p></o:p></p>
<p class="MsoNormal">Example: EPSG:2218<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">With some CRS of type PJ_TYPE_VERTICAL_CRS I get the error code "Unknown error (code 4096)".<o:p></o:p></p>
<p class="MsoNormal">Here the error code tells me even less what the problem is.<o:p></o:p></p>
<p class="MsoNormal">Examples: EPSG:5620<o:p></o:p></p>
<p class="MsoNormal"> EPSG:6357 (here I also received the log message "pipeline: Pipeline: Mismatched units between step 3 and 4" from Proj9)<o:p></o:p></p>
<p class="MsoNormal"> <o:p></o:p></p>
<p class="MsoNormal">2.<o:p></o:p></p>
<p class="MsoNormal">When transforming to type PJ_TYPE_VERTICAL_CRS, the axes seem to be swapped in the result.<o:p></o:p></p>
<p class="MsoNormal">I used the same WGS84 coordinate for all tests (x=14, y=52, z=100 => Germany, Brandenburg).<o:p></o:p></p>
<p class="MsoNormal">The transformed coordinates were all x=52 and y=14. Is this intentional?<o:p></o:p></p>
<p class="MsoNormal">Some transformed coordinates also contained only Infinity.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Thanks in advance for your help.<o:p></o:p></p>
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