[R] persp graphs

[Mario Alberto Cozzuol]

Hi,
I am doing my way on R, with much experimenting. So, I am trying to plot a 3d 
graphic ussing "persp" and entering a data set (attached) of UTM coordinates 
as x,y and a pH values as z. However when I try an error message comes out 
telling that increasing x and y values are expected. Jus ordering the first 
vector does not help, and, of course, order the first two independently makes 
no sense since they are geographic coordinates. So, what I am doing wrong?
Thank you all very much for the help,

Mario
-- 
Dr. Mario A. Cozzuol
Laboratório de Biologia Evolutiva
Universidade Federal de Rondônia
BR 364, Km 9,5
78900-000 Porto Velho, RO
Brasil
Tel./Fax 55 69 217-8593 
E-mail mario at unir.br