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Simplify choose, and add gen_choose for fractional amounts

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This commit is contained in:
Grant Sanderson 2022-01-18 10:13:17 -08:00
parent eab97faf13
commit 872c949fb8
1 changed files with 7 additions and 4 deletions
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11
manimlib/utils/simple_functions.py
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@ -22,15 +22,18 @@ def choose_using_cache(n, r):
def choose(n, r, use_cache=True): def choose(n, r, use_cache=True):
if use_cache: if use_cache:
return choose_using_cache(n, r) return choose_using_cache(n, r)
if n < r: r = min(r, n - r)
return 0
if r == 0:
return 1
denom = reduce(op.mul, range(1, r + 1), 1) denom = reduce(op.mul, range(1, r + 1), 1)
numer = reduce(op.mul, range(n, n - r, -1), 1) numer = reduce(op.mul, range(n, n - r, -1), 1)
return numer // denom return numer // denom
def gen_choose(n, r):
numer = np.prod(np.arange(n, n - r, -1))
denom = np.prod(np.arange(1, r + 1))
return numer / denom
def get_num_args(function): def get_num_args(function):
return len(get_parameters(function)) return len(get_parameters(function))