moving raster maps across UTM zone boundaries

Fred Ogden flogden at
Thu Apr 15 12:45:53 EDT 1993

Hello fellow GRASS users.

	I've been fortunate in the past to have data sets well within UTM zones.
Unfortunately, that happy period is at an end.  I am dealing with county soils
and land use data for Oklahoma which is split between zones 14 and 15.  What I 
want to do is bring the raster map for a county in zone 15, and patch it with
a raster map in zone 14.  I've tried this procedure:

1) used r.poly to convert the zone 15 map to a vector map.
2) used v.out.ascii to convert the grass vector map to ascii.
3) used m.u2ll to convert the ascii vector UTM map to lat.-lon. coordinates
4) used m.ll2u to convert lat-lon. ascii vector map to zone 14 utm coordinates
5) used to convert new zone14 ascii vector map to grass vector map.

Now, I'm stuck.  The manual hints that I should apply v.digit to re-assign
attributes to the vector map before using  BUT, I'm dealing with 
_thousands_ of cells.  Is there a better way to do this whole process?  Or
does anyone have any suggestions?  I suspect this question may be posted
frequently, but I only recently began monitoring this discussion.  Thanks in 
advance for any and all replies.


Fred L. Ogden
Iowa Institute of Hydraulic Research
The University of Iowa
Iowa City, IA 52242

flogden at

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