I need to compute combinatorials (nCr) in Python but cannot find the function to do that in 'math', 'numyp' or 'stat' libraries. Something like a function of the type:

```
comb = calculate_combinations(n, r)
```

I need the number of possible combinations, not the actual combinations, so `itertools.combinations`

does not interest me.

Finally, I want to avoid using factorials, as the numbers I'll be calculating the combinations for can get to big and the factorials are going to be monstruous.

Any clue what function from what library I should use?

Many thanks

Exactly what I was looking for. Thanks!