add: slices advanced ops

16-slices/14-copy/02-hacker-incident/main.go

@@ -0,0 +1,56 @@
+// For more tutorials: https://blog.learngoprogramming.com
+//
+// Copyright © 2018 Inanc Gumus
+// Learn Go Programming Course
+// License: https://creativecommons.org/licenses/by-nc-sa/4.0/
+//
+
+package main
+
+import (
+	"fmt"
+
+	s "github.com/inancgumus/prettyslice"
+)
+
+func main() {
+	// #1: received the raining probabilities
+	data := []float64{10, 25, 30, 50}
+
+	// #2: received new data
+	// newData := []float64{80, 90}
+	// for i := 0; i < len(newData); i++ {
+	// 	data[i] = newData[i]
+	// }
+
+	// #3: use copy
+	// copy(data, []float64{99, 100})
+
+	// #4: received more data than the original
+	// copy(data, []float64{10, 5, 15, 0, 20})
+
+	// #5: returns the # of copied elements
+	// n := copy(data, []float64{10, 5, 15, 0, 20})
+	// fmt.Printf("%d probabilities copied.\n", n)
+
+	// #6: (sometimes) use append instead of copy
+	// data = append(data[:0], []float64{10, 5, 15, 0, 20}...)
+
+	// #7: clone a slice using copy
+	// saved := make([]float64, len(data))
+	// copy(saved, data)
+
+	// #9: clone a slice using append nil (i prefer this)
+	// saved := append([]float64(nil), data...)
+
+	// data[0] = 0 // #8
+
+	// s.Show("Probabilities (saved)", saved) // #7
+
+	// #1: print the probabilities
+	s.Show("Probabilities (data)", data)
+
+	fmt.Printf("Is it gonna rain? %.f%% chance.\n",
+		(data[0]+data[1]+data[2]+data[3])/
+			float64(len(data)))
+}