[gdal-dev] New user query about OGR library NTF import
ajc200 at maths.leeds.ac.uk
Sat Nov 14 13:10:55 EST 2009
I was hoping someone might be able to help me with a query about using the
OGR library to read an Ordnance Survey Landform Profile file in NTf format:
The file contains a 501 X 501 grid with height values at each point. From
the technical reference on the OS web page it lists this as being stored
within a field called Z_COORD. Manually inspecting the NTF file (which is
plain text) I can see values like 00159 meaning 15.9m AOD. If I run the
NTF through OGRINFO -al on the file produces a feature for this point:
HEIGHT (Integer) = 15
POINT (310000.0 490000.0 15.899999618530273)
At the moment I can't understand why it's writing out the height as an
integer, and also where the many decimal places in the z coordinate of the
point have come from.
Any help would be much appreciated.
I'm relatively new to GIS software; sorry if this is a silly question!
More information about the gdal-dev