Math symbols for labels in Perspective plots

Dear Harsh:

I stole these lines from the Persp examples and 
the plotmath examples.

     x <- seq(-10, 10, length= 30)
     y <- x
     f <- function(x,y) { r <- sqrt(x^2+y^2); 10 * sin(r)/r }
     z <- outer(x, y, f)
     z[is.na(z)] <- 1
     op <- par(bg = "white")
     persp(x, y, z, theta = 30, phi = 30, expand = 0.5, col = "lightblue")
     persp(x, y, z, theta = 30, phi = 30, expand = 0.5, col = "lightblue",

+            ltheta = 120, shade = 0.75, ticktype = "detailed",
+            xlab = "X", ylab = "Y", zlab = "Sinc( r )"
+      ) -> res

?plotmath
title( expression(paste(plain(sin) * phi, "  and  ",

+                                      plain(cos) * phi)))

Hope this helps!

By the way, this is from Windows.

Sincerely,
Erin Hodgess
Associate Professor
Department of Computer and Mathematical Sciences
University of Houston - Downtown
mailto: hodgess at gator.uhd.edu


Subject: [R] Math symbols for labels in Perspective plots


Hi ..
  
     I would like to have math symbols in perspective plots
  
  i tried :  persp(x,y,z,xlab=expression(phi))
  
  but it plots it as phi.
  
  Thanks.
  
  Harsh
  
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