Built-in module to calculate the least common multiple
In Python 3.8 and earlier
There is no such thing built into the stdlib.
However, there is a Greatest Common Divisor function in the
math library. (For Python 3.4 or 2.7, it's buried in
fractions instead.) And writing an LCM on top of a GCD is pretty trivial:
def lcm(a, b): return abs(a*b) // math.gcd(a, b)
Or, if you're using NumPy, it's come with an
lcm function for quite some time now.
Try this instead:
def lcm(x, y): from fractions import gcd # or can import gcd from `math` in Python 3 return x * y // gcd(x, y)
In Python 3.9+
This is available as
math.lcm(). It also takes any number of arguments, allowing you to find the lowest common multiple of more than 2 integers.
>>> from math import lcm >>> lcm(2, 5, 7) 70