Hello,

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:

http://www.ordnancesurvey.co.uk/oswebsite/products/landformprofile/techinfo.html

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:

OGRFeature)DTM_SD19SW):1
  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!

Many thanks,
Alex
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