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Le 02/12/2010 20:14, Paul Kelly a écrit :
<blockquote
cite="mid:Pine.LNX.4.62.1012021904190.5421@vortex.ukshells.co.uk"
type="cite">
<br>
On Thu, 2 Dec 2010, Thibault Lemaitre wrote:
<br>
<br>
<blockquote type="cite">I updated the tutorial in question. There
was some problem in the previous version : the modification of
the PROJ_INFO file was not good and the grid file needs to be in
the nad directory of GRASS. The method explained by the
tutorial, needs the administrator rights on Linux.
<br>
<br>
Somebody knows more about the nadgrids specification in the
PROJ_INFO file ? I mean, how to set a grid which is not in the
nad directory of GRASS ? If there is this possibility, a simple
normal user would be able to that.
<br>
</blockquote>
<br>
You should be able to just put the full path in the PROJ_INFO file
- does that not work? If not can you post the contents of the
PROJ_INFO file to the list.
<br>
</blockquote>
I first try with "/usr/share/proj/ntf_r93.gsb".<br>
I didn't try with something like "../../ntf_r93.gsb" (with the grid
put in the grassdata folder). Should I try it or it's useless and
won't work?<br>
<blockquote
cite="mid:Pine.LNX.4.62.1012021904190.5421@vortex.ukshells.co.uk"
type="cite">
<br>
We should probably include the French gridshift file for datum
transformations NTF <--> RGF93 in the GRASS distribution,
like we do for the USA, Canada, New Zealand files. That would make
it very easy to use. How large is the file?
<br>
</blockquote>
Like I write on the <a
href="http://grass.osgeo.org/wiki/IGNF_register_and_shift_grid_NTF-RGF93">tutorial</a>,
the grid can be found on the IGN Lambert 93 website. It weight 271
Kio (small enough, no ?). Integrate this in grass is a good idea.<br>
There is still a problem: this grid is not specified in the EPSG
spec. but only in the IGNF register (76 Kio) (see the tutorial for
more information).<br>
As I report in the <a
href="http://trac.osgeo.org/grass/ticket/1219">ticket 1219</a>,
proj integrate this (both the grid and the register), but not GRASS.
In fact, when you use the EPSG location wizard, it would be very
useful to be able to choose the IGNF register (/usr/share/proj/IGNF)
instead of the epsg. I tried to select the IGNF file, but it doesn't
work (may be a parse problem). I would like to help the developers
on this subject, but I don't really know how to do more than an
enhancement ticket.<br>
<br>
Thibault.<br>
<blockquote
cite="mid:Pine.LNX.4.62.1012021904190.5421@vortex.ukshells.co.uk"
type="cite">
<br>
Paul
<br>
<br>
<br>
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