以最小宽度浮动到Golang中的字符串

Question

I'm trying to get a float to print using fmt.Printf with a minimum width of 3

fmt.Printf("%3f", float64(0))

Should print 0.00, but it instead prints 0.000000 If I set the precision to 3, it truncates the value.

Basically, what I want is if the value is 0, it should print 0.00. If the value is 0.045, it should print 0.045, etc.

Answer 1

This function should do what you want:

func Float2String(i float64) string {
    // First see if we have 2 or fewer significant decimal places,
    // and if so, return the number with up to 2 trailing 0s.
    if i*100 == math.Floor(i*100) {
        return strconv.FormatFloat(i, 'f', 2, 64)
    }
    // Otherwise, just format normally, using the minimum number of
    // necessary digits.
    return strconv.FormatFloat(i, 'f', -1, 64)
}