[R] ggplot2 and geom_tile

[Øystein Godøy]

Dear community,

I have been using ggplot2 for visualisation and I am really impressed by this. 
I do however have a problem that returns when plotting various types of 
spatial datasets as raster images. This is probably due to me not fully 
understanding the package.

When I am plotting images using geom_tile, I sometimes only have small dots in 
the image and at other times I have apparently blank images. On other 
occasions it works nicely without me being able to spot the differences 
between these plot requests nor the underlying data. I am usually plotting 
geophysical information either on a geographical grid (latitude/longitude) or 
on a map projection (normally using proj4 for the projection of data). 

I have tried to play with the position attribute, but without success so far, 
but believe that I suffer from some form of effect from this. I have tried to 
google for information and I have read the manual pages but so far without 
success. Do you have some suggested reading for problems like this? Is the 
problem likely to be related to position?

I apologise for the vague description of the problem.

All the best
Øystein
-- 
Dr. Oystein Godoy
Norwegian Meteorological Institute 
P.O.BOX 43, Blindern, N-0313 OSLO, Norway
Ph: (+47) 2296 3000 (switchb) 2296 3334 (direct line)
Fax:(+47) 2296 3050 Institute home page: http://met.no/