[R] Beginner Question on Persp()

[rolf at math.unb.ca]

Your ``z'' which was read in by read.delim() is a *data frame*
not a matrix.

Do z <- as.matrix(z), then persp(x,y,z) will work.

				cheers,

					Rolf Turner
					rolf at math.unb.ca

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Original message:

> I recently downloaded R for Windows, running on Win XP.  I'm trying to create
> a perspective plot but not having any luck after reading the R manual and
> several examples found on the Internet.
> 
> I have a 100 x 100 matrix of Z data as a tab-delimited text file exported
> from Minitab.  I read this in to R using read.delim; this seemed to go ok. 
> I created  X and Y using seq() to get 100 divisions for the X and Y axes. 
> Again, everything looked good, when I typed X or Y I got a string of 100
> numbers.
> 
> However, when I try to do persp(x,y,z) I get an error something like: (list)
> cannot be coerced to double.  I know the basic data (matrix of z values) is
> ok (no hidden non-numeric values) because Minitab will graph it just fine. 
> Any suggestions on how to proceed?  Thanks in advanced for your help.