[GRASSLIST:3463] Re: NMEA log to GRASS vector?

[Al Green]

> Looking for an NMEA log reader for GRASS.
> I have a log from a GPS in NMEA format, which I understand is latitude
> longitude in WGS 84 datum, and my GRASS mapset is in UTM AGD 66.  How
> would I convert this to a GRASS vector file?

I haven't used it, but s.in.garmin.sh exists. 

Instead of having a laptop recording NMEA sentences, try downloading the
track data directly (can't speak for the log frequency). There is a
package called GPStrans out there (for linux) which will do this for you.
see http://sourceforge.net/projects/gpstrans


> There are 9047 points to convert, and I'd like to be able to do it with
> more data yet to be captured in NMEA format.

Grass's m.proj didn't do things to my liking (lat/lon wouldn't let me
specify wgs84) but I've found a program (free [as in beer]) for MSDOS
which works great- did the whole file at once. It's called Concord2; see:
http://www.linz.govt.nz/services/surveysystem/geodetic/snap/
(Note: Kiwi-centric, but you may be able to modify the definition file to
fit)

What I did was write a wee program to extract the time stamp/locations
from my NMEA log file, then saved those to a file and ran that file
through concord2. Worked quite well. I wrote it in Matlab, but it should
work in Linux with the Octave package. feel free to grab it if you want:
http://bambi.otago.ac.nz/hamish/read_gps.m

fyi the NMEA faq is at http://vancouver-webpages.com/peter/nmeafaq.txt

after that, s.in.ascii ...

g'luck.


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