[GRASS-user] Extracting line heights from 3d vectors

[Nick Cahill]

Hi all,

I have a series of contour vector maps imported from a CAD program  
(Microstation). The CAD maps were in 3d, and the 3d information was  
successfully imported into GRASS, so the vectors have line heights as  
well as length, etc. Now I need to export these into shapefiles. When  
I do this, all the other useless CAD data like line color, style,  
weight, etc. is exported as attributes in the .dbf file, but line  
height is not -- it is not a field in the mySQL database but is part  
of the geometry of the line, if I understand what's going on here  
correctly. Is there a way to transfer line height into the attribute  
table so I can access and export it? Many thanks,

Nick Cahill
Dept. of Art History
UW-Madison