new tasks

Task/Classes/R/classes-2.r

@@ -0,0 +1,24 @@
+setClass("circle",
+   representation(
+      radius="numeric",
+      centre="numeric"),
+   prototype(
+      radius=1,
+      centre=c(0,0)))
+#Instantiate class with some arguments
+circS4 <- new("circle", radius=5.5)
+#Set other data slots (properties)
+circS4@centre <- c(3,4.2)
+
+#Define a method
+setMethod("plot", #signature("circle"),
+   signature(x="circle", y="missing"),
+   function(x, ...)
+   {
+      t <- seq(0, 2*pi, length.out=200)
+      #Note the use of @ instead of $
+      plot(x@centre[1] + x@radius*cos(t),
+         x@centre[2] + x@radius*sin(t),
+         type="l", ...)
+   })
+plot(circS4)