Data update

Task/Average-loop-length/Pluto/average-loop-length.pluto

@@ -0,0 +1,39 @@
+require "table2"
+local fmt = require "fmt"
+
+local nmax <const> = 20
+
+local function avg(n)
+    local tests = 1e4
+    local sum = 0
+    for _ = 1, tests do
+        local v = table.rep(nmax, false)
+        local x = 1
+        while !v[x] do
+            v[x] = true
+            sum += 1
+            x = math.random(1, n)
+        end
+    end
+    return sum / tests
+end
+
+local function ana(n)
+    if n < 2 then return 1 end
+    local term = 1
+    local sum = 1
+    for i = n, 2, -1 do
+        term *= (i - 1) / n
+        sum += term
+    end
+    return sum
+end
+
+print(" N    average    analytical    (error)")
+print("===  =========  ============  =========")
+for n = 1, nmax do
+    local a = avg(n)
+    local b = ana(n)
+    local e = math.abs(a - b) / b * 100
+    fmt.print("%3d %9.4f  %12.4f   (%6.2f%%)", n, a, b, e)
+end