[R-sig-Geo] Mapping contours from jpg map

[Sarah Papworth]

Dear all,

I have a jpg map of altitudinal contours in my study area which I
would like to map and use in R to calculate the altitude and slope of
GPS coordinates.
So far, I have painstakingly traced these contours in ArcMap to create
a shapefile (of polylines) with altitude. I have now imported this
file shapefile into R.

 What I would like to do is turn it into a raster of slope and
altitude, but I can't seem to find any method of doing this in the
online R help archives. Does anyone have any idea which package I
should be using, or perhaps if it is even possible to turn this type
of shapefile into a raster?

Thanks in advance!

Sarah


-- 
Imperial College London
http://www.iccs.org.uk/sarahpapworth.htm