[R-sig-Geo] How do I read/work with PolyLineZM with maptools/sp?

[Mikhail Titov]

> I would try s$M and s$Z to access M and Z when they are attributes.
But what do I do when they are not? It can work for points, but not a line as I can't have attributes for individual points of a line. I would prefer not to do any extra conversions in GIS before using R.

Do I get it right that for now it is better to stick with shapefiles to read PolylineZM?

Mikhail