[GRASS-user] "v.transform" reports erroneous values in the transformation matrix

[Jose M Michia Roberts]

2013/2/26 Markus Metz <markus.metz.giswork en gmail.com>:
> Note that there are two transformation matrices, one for forward
> transformation, one for backward transformation. Can the PostGIS
> ST_Affine function print both matrices?

AFAIK, PostGIS cannot print neither calculate transformation matrices.
User must obtain matrices values from somewhere. [sorry if this thread
became off-topic]

> If possible, rather use v.rectify in GRASS 7 instead of v.transform in GRASS 6.
> With a recent version of GDAL/OGR, you can also add GCPs to a
> datasource with ogr2ogr -gcp which should then automatically transform
> the coordinates.

I will try it. Thank you for update me!

Salud!
Jose