June 2018 Update

Task/Monte-Carlo-methods/Go/monte-carlo-methods-2.go

@@ -0,0 +1,34 @@
+package main
+
+import (
+    "fmt"
+    "math"
+    "time"
+
+    "golang.org/x/exp/rand"
+)
+
+func getPi(numThrows int) float64 {
+    inCircle := 0
+    for i := 0; i < numThrows; i++ {
+        //a square with a side of length 2 centered at 0 has
+        //x and y range of -1 to 1
+        randX := rand.Float64()*2 - 1 //range -1 to 1
+        randY := rand.Float64()*2 - 1 //range -1 to 1
+        //distance from (0,0) = sqrt((x-0)^2+(y-0)^2)
+        dist := math.Hypot(randX, randY)
+        if dist < 1 { //circle with diameter of 2 has radius of 1
+            inCircle++
+        }
+    }
+    return 4 * float64(inCircle) / float64(numThrows)
+}
+
+func main() {
+    rand.Seed(uint64(time.Now().UnixNano()))
+    fmt.Println(getPi(10000))
+    fmt.Println(getPi(100000))
+    fmt.Println(getPi(1000000))
+    fmt.Println(getPi(10000000))
+    fmt.Println(getPi(100000000))
+}