I have a file with 3 cols as:
x    y    value
1    1    0.5000
1    2    1.8333
1    3    4.3333
2    1    0.7500
2    2    0.7500
2    3    4
3    1    0.7500
3    2    1.4167
3    3    5.1667

I read them in using
p <- read.table("data.txt", header=TRUE)

My questoin: how to draw a image to show the values at different positions
(x, y)? I would like to see different colors for different values.

Sorry if it is a naive question, but it is my first week of R and I have
been trying for several hours trying to make it.

Thank you,
-- 
Senlin Liang

	[[alternative HTML version deleted]]


