这是发行5391：fmt：Scanf拒绝\r\n在Windows上线的末端。
作为一种解决方法，要检查输入是否有效，请编写，
var inputSquare float64
n, err := fmt.Scanf("%f\n", &inputSquare)
if err != nil || n != 1 {
// handle invalid input
fmt.Println(n, err)
}
和
var inputGuess float64
n, err = fmt.Scanf("%f\n", &inputGuess)
if err != nil || n != 1 {
// handle invalid input
fmt.Println(n, err)
}
解决方法是"%f\n"格式字符串中的换行符。
包 fmt
func Scanf(format string, a ...interface{}) (n int, err error)
Scanf扫描从标准输入读取的文本，将连续的以空格分隔的值存储到由格式确定的连续的参数中。它返回成功扫描的项目数。
这是一个完整的工作程序：
package main
import (
"fmt"
)
// compute square roots by using Newton's method
func main() {
var x float64 //number to take square root
var y float64 //this is the guess
var q float64 //this is the quotient
var a float64 //this is the average
fmt.Print("Enter a number to take its square root: ")
var inputSquare float64
n, err := fmt.Scanf("%f\n", &inputSquare)
if err != nil || n != 1 {
// handle invalid input
fmt.Println(n, err)
return
}
fmt.Print("Enter first guess ")
var inputGuess float64
n, err = fmt.Scanf("%f\n", &inputGuess)
if err != nil || n != 1 {
// handle invalid input
fmt.Println(n, err)
return
}
x = inputSquare
y = inputGuess
for i := 0; i < 10; i++ {
q = x / y // compute the quotient; x and y are given
a = (q + y) / x // compute the average
y = a // set the guess to the average
}
fmt.Printf("sqrt(%g) = %g\n", x, y)
}
输出：
Enter a number to take its square root: 2.0
Enter first guess 1.0
sqrt(2) = 1.414213562373095
我在Windows 7上使用Go 1.1.1：
C:\>go version
go version go1.1.1 windows/amd64
602392714
清零编程群