Change a variable given in a function

Question

I want to make a function that checks if a random number is within a certain value and if it is then reroll the number for that variable.

But I don’t know how to set the input variable without calling its name directly.

code:

def checkVal(value,max,min):
    if value<max or value>min:
        value=random.randrange((-30/10),(30/10))
        checkVal(value,min,max)
    else:
        pass

Asked By: Myskal Muskal

||

Source

Answer 1

You can’t charge a variable from within a function without using a global, however this wouldn’t be good practice here. Rather return your value.

Also your test would always be True if max>min, you probably meant to swap the conditions (lower > value or value > upper).

def checkVal(value, upper, lower):
    if lower > value  or value > upper):
        value = random.randrange((-30/10),(30/10))
        return checkVal(value, upper, lower)
    return value

value = checkVal(value, upper, lower)

From an algorithmic point of view, using a recursive function as a loop is also not so good practice. Rather use a while loop:

def checkVal(value, upper, lower):
    while lower > value  or value > upper:
        value = random.randrange((-30/10),(30/10))
    return value

value = checkVal(value, upper, lower)

Finally, you can probably remove the loop entirely by choosing directly the correct bounds:

def checkVal(value, upper, lower):
    if lower > value  or value > upper:
        value = random.randrange(max(lower, (-30/10)), min(upper, (30/10)))
    return value

value = checkVal(value, upper, lower)

Answered By: mozway

Change a variable given in a function

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