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Hello,
I have a problem here, indeed, I used an ASCII file from LIDAR data but I want now to define a coordinate system. When I open the ASCII file, it gave me a list of numbers :
545023.50 299909.50 8.33
545024.50 299909.50 8.70
545025.50 299909.50 8.80
545026.50 299909.50 8.79
545027.50 299909.50 9.01
545028.50 299909.50 8.41
545029.50 299909.50 8.52
545030.50 299909.50 8.54
545031.50 299909.50 9.11
...
I understand that it is X, Y and Z coordinates but I don't know in which coordinate system. Does anyone have an idea ?
(It is supposed to be in the North of France, on the coast)
Thanks in advance,
Take care,
Joss
Have you checked with the data provider?
Robert,
How did you manage to use UTM? Northing values in northern France should be around 5.5million. So if I swap the order of the coordinates so that they're in northing easting z order, and add 5 million to the northings, than UTM 31 North looks like it might work.
Other French systems just don't seem to fit, even if I swap the xy values.
Melita
Hi Joss,
Well, I tried both, and neither looks too hopeful. One landed offshore in the Channel (north of Le Havre) and the other in the middle of northern France. Here's how I did it. I added the points as an event layer using Add XY Data in ArcMap. When setting the coordinate system, I choose WGS 1984 UTM Zone 31N, but then modified it to have a false northing of -5000000. Then I added the data again, but switched columns for the x and y values, again using the modified false northing.
Can you narrow down the location beyond the coast of northwest France? Depending on how I look at it, I think it could be anywhere between Brest and Le Havre.
Melita