[GRASS-dev] error in georeferencing points on import with v.in.ascii

Markus Metz markus.metz.giswork at gmail.com
Sat Jun 8 12:37:35 PDT 2013

On Sat, Jun 8, 2013 at 8:55 PM, Michael Barton <Michael.Barton at asu.edu> wrote:
> I just came across something that is very disturbing.
> I imported a batch of points from a CSV file.
> 2 points have the same geographic location (they are a single archaeological
> site occupied at different time periods)
> I import them into a UTM Zone 30 European Datum 1950 location and they are
> georeferenced using the following values:
> x coordinate = -31415 and y coordinate = 4116150
> Once they are in GRASS, however, they show up in 2 different places on my
> map. I captured the coordinates from the screen and did a query on both
> points and the results agree. Here are the reported locations of the 2
> points
> East = -31418.8180586,  North = 4116177.13863
> East = -30639.9940711, North = 4116551.27956
> The coordinates are significantly different from each AND from the imported
> coordinates of the 2 points. It looks like one of the points is place close
> to (but not exactly) on the original north coordinate and the other points
> is placed close to (but not exactly) on the original east coordinate.
> What is going on here???

Can you provide CSV file with the 2 points and the exact commands you
used? A simple import should not change the coordinates.

Markus M

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