[GRASS-dev] G_units_to_meters_factor

Glynn Clements glynn at gclements.plus.com
Wed Sep 21 15:35:19 EDT 2011

G_units_to_meters_factor() (in lib/gis/units.c, in 7.0) has:

    case U_FEET:
	return 3.28083989501312;	        /*  1 / (0.0254 * 12)    */

This is correct for the international foot but, AFAIK, most (but not
all) non-metric geographical data uses the US survey foot.

IMHO, we need both U_FEET and e.g. US_USFEET. Possibly also for miles. 
Or even U_INTFEET and U_USFEET; calling one of them just "feet"
creates a risk of users selecting the "default" rather the correct

Glynn Clements <glynn at gclements.plus.com>

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