rand

077-rand.go

@@ -1,26 +1,37 @@
-                                                    // The `math/rand` package provides psuedo-random numbers.
+package main                        // The `math/rand` package provides psuedo-random
-
+                                    // numbers.
-package main
-
 import (
 	"math/rand"
 	"fmt"
 )
 
 func main() {
-	fmt.Println(rand.Intn(100))                     // For example, `rand.Intn` returns a random `int` n,
+	fmt.Print(rand.Intn(100), ",")  // For example, `rand.Intn` returns a random `int` n,
-	fmt.Println(rand.Intn(100))                     // `0 <= n < 100`.
+	fmt.Print(rand.Intn(100))       // `0 <= n < 100`.
+    fmt.Println()
+
+	fmt.Println(rand.Float64())     // `rand.Float64` returns a `float64` `f`,
+	                                // `0.0 <= f < 1.0`.
+                                    
+    s1 := rand.NewSource(42)        // To make the psuedo-random generator deterministic,
+	r1 := rand.New(s1)              // give it a well-known seed.
 											   
 	
-	fmt.Println(rand.Float64())                     // `rand.Float64` returns a `float64` `f`, `0.0 <= f < 1.0`.
+	fmt.Print(r1.Intn(100), ",")    // Call the resulting `rand.Source` just like the
+	fmt.Print(r1.Intn(100))         // functions on the `rand` package.
+    fmt.Println()
 
-	r1 := rand.New(rand.NewSource(int64(1337)))     // To make the psuedo-random generator deterministic, give it a
+    s2 := rand.NewSource(42)        // If you seed a source with the same number, it
-												    // well-known seed.
+	r2 := rand.New(s2)              // produces the same sequence of random numbers.
-	
+	fmt.Print(r2.Intn(100), ",")                  
-	fmt.Println(r1.Intn(100))                       // Call the resulting `rand.Source` just like the functions on
+	fmt.Print(r2.Intn(100))
-	fmt.Println(r1.Intn(100))                       // the `rand` package.
+	fmt.Println()
-
-	r2 := rand.New(rand.NewSource(int64(1337)))     // If you seed a source with the same number, it produces the
-	fmt.Println(r2.Intn(100))                       // same sequence of random numbers.
-	fmt.Println(r2.Intn(100))
 }
+
+/*
+$ go run rand.go
+81,87
+0.6645600532184904
+5,87
+5,87
+*/