Dear R-users,

I build already many contour graphs using the contour-procedure in R (akima library), after interpollating my data z on x,y (see e.g. graphs in this paper: http://www.biomedcentral.com/content/pdf/1471-2148-9-16.pdf).

Now, however, i experience unexpected and completely unsensible problems: after building the syntax, i can create the graphs and use the interp-command without any problems. However, after shutting down R and opening the saved syntax (that worked), i now get the error message that the 'interp.old' doesn't calculate due to collinearity in the data (which is not the case). So, i am now unable to create the graphs that i was used to build.

Has anyone got this problem before and, if yes, how was it solved?

Many thanks for the help,
Dries
	[[alternative HTML version deleted]]

