Dear GRASS community,
I recently found some vector data of an area that i’m interesting, in a X-Y unreferenced system, and i want to “put” them in my mapset (UTM - Zone 34 - International), that i’m working.
How i can transform them, so i can use them with my rest vector data?
I would very appreciate any ideas about this.
Thank you in advance,
Vangelis.
Hello, Vangelis!!
you can use the v.transform to do such a thing...
you must have some reference points in the map to be transformed..
good luck!!!
Vangelis Filippidis wrote:
Dear GRASS community, I recently found some vector data of an area
that i'm interesting, in a X-Y unreferenced system, and i want to
"put" them in my mapset (UTM - Zone 34 - International), that i'm
working. How i can transform them, so i can use them with my rest
vector data? I would very appreciate any ideas about this. Thank you
in
advance,Vangelis. ------------------------------------------------------------------------Filippidis Evangelos
Forester, Ph.D Candidate
Sector of Planning & Natural Resource Development
Department of Forestry & Natural Environment
School of Geotechnical Sciences
Aristotle University of Thessaloniki
Greece
e-mail : efilippi@for.auth.gr-----------------------------------------------------------------------
-----------------------------------------
Sungwon Choi
GIS LAB, Center for mineral resources center
Korea university, Korea
tel : +81-2-953-1676
-----------------------------------------
Vangelis Filippidis wrote:
Dear GRASS community,
I recently found some vector data of an area that i'm interesting,
in a X-Y unreferenced system, and i want to "put" them in my mapset
(UTM - Zone 34 - International), that i'm working.
How i can transform them, so i can use them with my rest vector
data?I would very appreciate any ideas about this.
Thank you in advance,
Vangelis.
Vangelis,
If you can locate at least 4 points on your "unreferenced" vector file
that you can get known UTM coordinates for,
you can use v.transform, however this will only work on an ascii file.
Bring your new file into your mapset as a binary vector coverage, then
convert the file to an ascii coverage using v.out.ascii. Determine at
least four reference points and make a file
called "points" or something in the format:
X1 Y1 UTM-Easting1 UTM-Northing1
X2 Y2 UTM-Easting2 UTM-Northing2
X3 Y3 UTM-Easting3 UTM-Northing3
X4 Y4 UTM-Easting4 UTM-Northing4
where each row is a different reference coordinate pair delimited by
spaces (no header or anything). Run the v.transform script to
generate a new ascii coverage. (It's easy to run interactively.) Then,
finally, use v.in.ascii to convert the newly referenced ascii file back
to a binary vector file. I did this a while back to convert a geodimeter
file to UTM and it is quite simple! I only used 4 points and got an RMS
of 2.9.
--
Katie Alvin
FOCS/FGI/GIS Specialist
USDA NRCS, Bozeman, MT
(406)587-6929
kalvin@mt.nrcs.usda.gov
ti les re sy vaggeli…
ena ktirio ypo8esi kai esy rwtas sto INTERNET!!!
Vasilis Yannakopoulos
Lab of Forest Management & Remote Sensing
Faculty of Forestry & Natural Environment
Aristotle University
University Campus Box 248
Thessaloniki 54006
GREECE
phone: +3031992689
fax: +3031998897
e-mail: vilouni@for.auth.gr
-----Original Message-----
From: grass@pandora.cecer.army.mil [mailto:grass@pandora.cecer.army.mil]On Behalf Of Vangelis Filippidis
Sent: Monday, December 07, 1998 11:37 PM
To: grass@cecer.army.mil
Subject: Transformation question…Dear GRASS community,
I recently found some vector data of an area that i’m interesting, in a X-Y unreferenced system, and i want to “put” them in my mapset (UTM - Zone 34 - International), that i’m working.
How i can transform them, so i can use them with my rest vector data?I would very appreciate any ideas about this.
Thank you in advance,
Vangelis.
Filippidis Evangelos
Forester, Ph.D Candidate
Sector of Planning & Natural Resource Development
Department of Forestry & Natural Environment
School of Geotechnical Sciences
Aristotle University of Thessaloniki
Greece
e-mail : efilippi@for.auth.gr