<div dir="ltr">I was able to get the actual pipeline transformation used by "cs2cs" by running: <br><div><i>projinfo -s EPSG:4326 -t EPSG:5174</i></div><div><br></div><div>Still, I'm having problems using the output proj string:<br><i>+proj=pipeline<br> +step +proj=axisswap +order=2,1<br> +step +proj=unitconvert +xy_in=deg +xy_out=rad<br> +step +proj=push +v_3<br> +step +proj=cart +ellps=WGS84<br> +step +inv +proj=molobadekas +x=-145.907 +y=505.034 +z=685.756 +rx=-1.162<br> +ry=2.347 +rz=1.592 +s=6.342 +px=-3159521.31 +py=4068151.32<br> +pz=3748113.85 +convention=coordinate_frame<br> +step +inv +proj=cart +ellps=bessel<br> +step +proj=pop +v_3<br> +step +proj=tmerc +lat_0=38 +lon_0=127.002890277778 +k=1 +x_0=200000<br> +y_0=500000 +ellps=bessel<br> +step +proj=axisswap +order=2,1</i></div><div><br></div><div>The error I get is "can't initialize operations that take non-angular input coordinates". If I remove the "unitconvert" step, I can run proj bin, but I get wrong results (even if I manually convert the input from degree to radians). Any suggestions?</div><div><br></div><div>Many thanks,</div><div>Roberto</div><div><br></div></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Fri, Sep 17, 2021 at 9:35 AM Roberto Toldo <<a href="mailto:roberto.toldo@3dflow.net">roberto.toldo@3dflow.net</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div dir="ltr">Hello!<br><br>I found some issues/differences from the "proj" bin and "cs2cs" bin utilities. I'm using the last version, directly compiled from Github.<br>Probably it's something due to my inexperience with the library, so please bear with me :)<br><br>Specifically, I was trying to convert coordinates from geodetic to EPSG:5174 ( Korean 1985 / Modified Central Belt).<br><br>I used proj with the parameters extracted from "projinfo EPSG:5174":<br>proj +proj=tmerc +lat_0=38 +lon_0=127.002890277778 +k=1 +x_0=200000 +y_0=500000 +ellps=bessel +units=m +no_defs<br><br>and then cs2cs with direct conversion parameters:<br>cs2cs +init=epsg:4326 +to +init=epsg:5174<br><br>However, I obtain quite different results.<br><br>For example, If I use lat_0 and lon_0 as input (127.002890277778, 38), I obtain exactly false_easting and false_northing (200000, 500000) when using proj4 (as expected), while I obtain something different when using cs2cs (200185.04 499695.19). <br>I would be expecting the same results. I tried with other coordinate systems (e.g., EPSG:32633 UTM zone 33N), and I noticed no differences between proj and cs2cs results.<br>Can anybody help me understand what the reason for the differences is? Are the parameters used internally by cs2cs different for EPSG:5174? I also tried setting the accuracy, but it doesn't seem to work.<br><div><br></div><div>Thanks,</div><div>Roberto</div><div><br></div></div>
</blockquote></div><br clear="all"><br>-- <br><div dir="ltr" class="gmail_signature"><div dir="ltr"><span style="font-family:arial,helvetica,sans-serif"><font size="1">Roberto Toldo<br>Technical Director & Co-founder | 3Dflow srl</font><br><font size="1">+39 </font></span><span style="font-family:arial,helvetica,sans-serif"><font size="1">045 4500109 | <a href="mailto:roberto.toldo@3dflow.net" target="_blank">roberto.toldo@3dflow.net</a> | <a href="http://www.3dflow.net" target="_blank">http://www.3dflow.net</a></font><font size="1">
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