Python conditionally round up numbers

Question

Today I have a question for you about rounding up numbers using conditions in Python.

I am doing a sales website and my client wants to round up the prices depending of the result converting them from USD to Colombian Pesos. For example: 200 USD to COP results in 353990 COP, and it should be rounded to 359000.

He have implemented a function that is doing the trick in Excel:

=IF(F4>=10000000,(ROUNDUP(F4,-6)-100000),IF(F4>=1000000,(ROUNDUP(F4,-5)-10000),IF(F4>=100000,(ROUNDUP(F4,-4)-1000),IF(F4>=10000,(ROUNDUP(F4,-3)-1000),IF(F4>=0,(ROUNDUP(F4,-3)))))))

I need to do exact the same thing but in Python, and I don't know the way to do it.

Thanks for helping me!

Answer 1

import math
roundup = lambda x: math.ceil(x/1000.0) * 1000

Although rounding 353990 to 359000 makes no sense. This function will round 353990 up to 354000.

If you want normal rounding rather than a 'round up', you would just use the builtin funciton round:

round(x, -3)

and so for a generic roundup with the same function signature as round

def roundup(x, n=0):
    return math.ceil(x * (10**n)) * (10**-n)

Answer 2

def round_up(value, multiple):
    return multiple * math.ceil(float(value) / multiple)

def digits(value):
    return int(math.log(value, 10)) + 1

def round_price(value):
    if value < 10000:
        return int(round_up(value, 1000))
    d = digits(value)
    new_value = int(round_up(value, 10 ** (d - 2)))
    new_value -= 10 ** (d - 3)
    return new_value