[R] contour plot - smooth lines

[tommaso.letterio at unifi.it]

Dear R-Users,
I am using 'contour' to plot a graph using values x,y and a matrix z.
I would like to obtain 'smooth lines' instead of no-smooth contour lines.
I tried with filled.contour too.
In a Post I found
yy <-predict(interpSpline(x, y))
I could use that method for each range that I want to plot but I hope  
to find a easier method.

Thank you

Tommaso Letterio
DIAF - UniFi
Via San Bonaventura 13
Firenze (IT) - 50145
+39-055-3288605