2016 Update

Task/Percolation-Mean-run-density/Go/percolation-mean-run-density.go

@@ -0,0 +1,35 @@
+package main
+
+import (
+    "fmt"
+    "math/rand"
+)
+
+var (
+    pList = []float64{.1, .3, .5, .7, .9}
+    nList = []int{1e2, 1e3, 1e4, 1e5}
+    t     = 100
+)
+
+func main() {
+    for _, p := range pList {
+        theory := p * (1 - p)
+        fmt.Printf("\np: %.4f  theory: %.4f  t: %d\n", p, theory, t)
+        fmt.Println("        n          sim     sim-theory")
+        for _, n := range nList {
+            sum := 0
+            for i := 0; i < t; i++ {
+                run := false
+                for j := 0; j < n; j++ {
+                    one := rand.Float64() < p
+                    if one && !run {
+                        sum++
+                    }
+                    run = one
+                }
+            }
+            K := float64(sum) / float64(t) / float64(n)
+            fmt.Printf("%9d %15.4f %9.6f\n", n, K, K-theory)
+        }
+    }
+}