[R] help working with persp plot function

[Steven K Friedman]

Hi, 

I don't understand why this is not working.  Help is appreciated. 

I need to plot the following as a surface, but persp returns an error. 

tpcp_xy[1:10,]
   X_COORD  Y_COORD TPCP
1  465459.7 175924.1 0.85
2  466145.8 324017.3 2.30
3  467720.2 372143.1 1.56
4  470293.2 348064.8 2.87
5  476566.9 205501.8 0.94
6  477774.9 142561.0 1.31
7  479207.0 162919.6 3.04
8  480890.8 290641.3 2.20
9  488865.9 159201.4 2.30
10 490328.3 248049.0 2.81 


Note that the X_COORD column is sorted in an increasing order. 

> objects(2)
[1] "TPCP"    "X_COORD" "Y_COORD"
> persp(X_COORD, Y_COORD, TPCP)
Error in persp.default(X_COORD, Y_COORD, TPCP) :
       increasing x and y values expected 

Ok so why is the function returning an error message? 

Thanks for your time and insights. 

Steve Friedman           email friedm69 at msu.edu
Department of Forestry
Michigan State University