[postgis-users] Using grids transformation method with PostGis

[Luís de Sousa]

Hello again,

I have tested this procedure in another PostGIS 1.4 install on Debian.
The results are exactly the same as on Ubuntu.

Is there any way I can test the usage of grid files? Some sort of
standard test procedure?

Thank you,

Luís

2010/6/9 Luís de Sousa <luis.a.de.sousa at gmail.com>:
>
> user at gisvm:/etc/profile.d$ cs2cs +init=pt:dlxhg +to +init=pt:pttm06
> -74584.120 2459.620
> -74582.57       2460.86 0.00
>
> user at gisvm:/etc/profile.d$ /etc/postgresql/8.4/bin/psql -h localhost
> -d template_postgis -p 5432 -U postgres
> Password for user postgres:
> psql (8.4.1)
> Type "help" for help.
>
> template_postgis=# UPDATE spatial_ref_sys
> template_postgis-# SET proj4text = '+proj=tmerc
> +lat_0=39.66666666666666 +lon_0=1 +k=1 +x_0=0 +y_0=0 +ellps=intl
> +pm=lisbon +units=m +no_defs +nadgrids=ptLX_e89.gsb'
> template_postgis-# WHERE srid = 20791;
> UPDATE 1
> template_postgis=# SELECT
> X(ST_Transform(PointFromText('POINT(-74584.120 2459.620)', 20791),
> 3763)),
> template_postgis-# Y(ST_Transform(PointFromText('POINT(-74584.120
> 2459.620)', 20791), 3763));
>         x         |        y
> -------------------+------------------
>  -74477.6196590331 | 2281.82581261726
> (1 row)
>