[GRASS-dev] v.to.db's foot

[Maciej Sieczka]

Hi

What is the foot in v.to.db? It's units.c reads:

case U_FEET:
     f      = 3.2808;

Which means the v.to.db's foot is 1/3.2808=0.304803706. What
"foot" is it? Grepping through PROJ.4's EPSG file, I find
the following possible values used in coordinate systems
around the world:

to_meter=0.3047972654
to_meter=0.3047994715386762
to_meter=0.3047997101815088
to_meter=0.3048
to_meter=0.3048006096012192

Neither seems to be the v.to.db one. Closest is the 4th one,
but for an exact match the ratio in units.c should be
3.280839895.



BTW: in $GISBASE/etc/proj-units.table there are 2
records for foot:

feet:foot:0.3048
USfeet:USfoot:0.34080060960121920243

Isn't the latter supposed to start with 0.3048... instead of
0.3408.. ?! Feet are puzzling.

Maciek