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Version 1.7.1  (2003-06-16)

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> invisible(options(echo = TRUE))
> 
>  source("fred.R")
> 
>  sum.fred <- fred(1:10, 1:5, 1:3)
>  sum.fred
[1] 4950
> 
>  sum <- 0
>  for (i in 1:10) {
+      for (j in 1:5) {
+          for (k in 1:3) {
+              sum <- sum + i * j * k
+          }
+      }
+  }
>  all.equal(sum, sum.fred)
[1] TRUE
> 
>  fred(1:10)
[1] 55
> 
>  sum.fred <- fred(1:10, 1:5, 1:3, func = sin)
>  sum.fred
[1] 0.4703183
> 
>  sum <- 0
>  for (i in 1:10) {
+      for (j in 1:5) {
+          for (k in 1:3) {
+              sum <- sum + sin(i) * sin(j) * sin(k)
+          }
+      }
+  }
>  all.equal(sum, sum.fred)
[1] TRUE
> 
>  ##### note: the following should crash
>  fred(func = sin)
Error in sum(func(w)) : Argument "w" is missing, with no default
Execution halted