[GRASS-user] scale error for each pixel

[Helmut Kudrnovsky]

Ken Mankoff wrote
> Dear GRASS List,
> 
> Does GRASS (or GDAL?, proj4?) have a function (or addon) to provide the
> scale error  for a given cell?
> 
> My understanding is that for a given projection, the "lat_ts" term of the
> proj4 string describing the projection is where 1 m in GRASS is actually 1
> m. Elsewhere, errors grow. I'd like to track these.
> 
>   -k.
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Doesn't it depends on the projection you're using?

Looking at e.g.

http://epsg.io/31287

there is no lat_ts factor as this is an area preserving projection.

AFAIR there is now an area function in r.mapcalc in GRASS trunk to calculate
the pixel area.

HTH




-----
best regards
Helmut
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