best data model for line segments with multiple attributes?

Or maybe I need a SpatialLineDataFrame (without the "s"!)?

If it is convenient for your problem, I would start with the
SpatialLinesDataFrame, as it is there right now and allows you to do
several things that might be useful to you or others. Then, continue
working on another, possibly derived, class, when the need arises.

Edzer Pebesma
Institute for Geoinformatics (ifgi), University of M?nster
Weseler Stra?e 253, 48151 M?nster, Germany. Phone: +49 251
8333081, Fax: +49 251 8339763  http://ifgi.uni-muenster.de
http://www.52north.org/geostatistics      e.pebesma at wwu.de