public static double readNumber(String prompt,double min, double max){

    Scanner scanner = new Scanner(System.in);
    double value;
    while (true){
        System.out.print(prompt);
        value = scanner.nextFloat();
        if (value >= min && value <= max) {
            break;
        } else
            System.out.println("Enter a value between " min " and " max);
    }
    return value;
}

The upper one works. But the following one doesn't jump out of the loop.

def readnumber(prompt, minimum, maximum):
    while True:
        value = float(input(prompt))
        if minimum <= value <= maximum:
            return value
        else:
            print(f"a valid value needed between {minimum} and {maximum}")
            break

It doesn't work the same way. HELP the new beginner please

CodePudding user response：

You have the break in the wrong case. in the java method you break when the value is > minimum and < than maximum, but in the python code you break the loop in the other case

CodePudding user response：

For me it works perfectly fine. To use the function just put it somewhere and make sure to make the prompt a string like for example in this usecase of the function:

print(readnumber("input a number: ", 2, 4))

Edit: For contiuos asking for a number remove the break statement in the else clause

CodePudding user response：

You could add an extra line of code and create a flag and change the flag e.g.,

flag = true

and use

while(flag)

Then instead of break, you can change the flag to false so the loop stops explicitly rather than implicitly