On 08/10/2018 05:45 PM, Rich Shepard wrote:
On Fri, 10 Aug 2018, Micha Silver wrote:

If I understand, you have a vector of points with x,y and z in the
attribute table, and you want to transform to some different coordinate
system, while also transforming the elevation.

  I must not yet be sufficiently cafinated this morning. When I look again
at the input and v.out.ogr files I now see that I had transformed the
elevation column to meters when my gawk script extracted columns from the
source data.

I was trying to point out that, regardless if the units are meters or feet, when you transform to a different CRS, you change all three values of the location, x,y and z.
For example:

micha@TP480:~$ echo "35.3 30.8 -180" | cs2cs +init=epsg:4326 +to +init=epsg:2039
228595.08    523262.05 -200.28 

In the EPSG 2039 CRS my elevation has "dropped" by 20 meters (!) compared to WGS84


Micha Silver
Ben Gurion Univ.
Sde Boker, Remote Sensing Lab
cell: +972-523-665918

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