<div dir="ltr"><br><div class="gmail_extra"><br><div class="gmail_quote">On Wed, Nov 2, 2016 at 9:48 AM, Bas Couwenberg <span dir="ltr"><<a target="_blank" href="mailto:sebastic@xs4all.nl">sebastic@xs4all.nl</a>></span> wrote:<br><blockquote style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex" class="gmail_quote"><span class="gmail-">On 2016-11-02 09:36, Roger Oberholtzer wrote:<br>
> I have updated to 4.9.3. My rdnap file is identical to yours:<br>
><br>
> # RDNAP with NTv2 and VDatum<br>
> <rdnap> +proj=sterea +lat_0=52.15616055555555 +lon_0=5.38763888888889<br>
> +k=0.9999079 +x_0=155000 +y_0=463000 +ellps=bessel<br>
> +nadgrids=rdtrans2008.gsb +geoidgrids=naptrans2008.gtx +units=m<br>
> +no_defs<br>
> <><br>
><br>
> If I run this:<br>
> cs2cs -r +init=epsg:4258 +to +init=rdnap:rdnap -f %.4f<br>
><br>
> And provide these locations:<br>
><br>
> 50.792584908 5.773795547 174.9478<br>
><br>
> I get this:<br>
><br>
> 182225.9086 311388.1617 128.9976<br>
><br>
> Not the values you listed:<br>
><br>
> 182260.4500 311480.6701 129.0000<br>
><br>
><br>
> I'm confused.<br>
<br>
</span>Does your epsg file use +towgs84 values for EPSG:4258?<br>
<br>
# ETRS89<br>
<4258> +proj=longlat +ellps=GRS80 +towgs84=0,0,0,0,0,0,0 +no_defs <><br>
<br>
I guess you're on Windows, which uses a different libc that may also<br>
explain the divergence.<br></blockquote><div><br></div><div>I'm on Linux. I see that when I updated my libproj, a new epsg file was installed. I don't usually use that file. I did here because I wanted to duplicate your exact command. 4258 is defined as:<br> <br></div><div><4258> +proj=longlat +ellps=GRS80 +towgs84=0,0,0,0,0,0,0 +no_defs <><br><br></div><div>I'm curious why you use both the definition in the epsg file, as well as the one in rdnap. Why not everything in the rdnap file? What is your definition for 4258?<br><br></div><div>If I change my command to:<br><br>cs2cs -r +to +init=rdnap:rdnap<br><br></div><div>I see that the grid shift file is now read. But my computed values are still:<br><br>182225.9086 311388.1617 128.9976<br><br></div></div><br><br clear="all"><br>-- <br><div class="gmail_signature">Roger Oberholtzer</div>
</div></div>