Never mind that. I thought when you mentioned calculus, you were talking about differentiation/integration.
Googling the definition made it make more sense - a particular method or system of calculation or reasoning.
My bad.

Typo?
There are several ways to determine the precision of the calculus but to keep things easy

I'm getting the same error as others in C++.

Expected: equal to 1.2125
Actual: 1.2125

Any ideas?

edit: I fixed it.

Fixed Tests: mean data1
London
48 38.9 39.9 42.2 47.3 52.1 59.5 57.2 55.4 62 59 52.9 
Testing at 1e-2; Expected should be 57.03333333, but got 51.2

Random Tests: mean data1
Beijing
3.9 4.7 8.2 18.4 33 78.1 224.3 170 58.4 18 9.3 2.7 
Testing at 1e-2; Expected should be 59.08333333, but got 52.41666667

I'm not sure what I'm doing wrong.

The Binomial Thereom/relationship between Pascal's Triangle and combinations is what I tried to do. One number overflows so I end up with a wrong answer.

Expected: equal to 28
Actual: 20

I've changed everything to std::uint64_t, but it still doesn't work.

Raw results before round() and log():

3432
10400600
2333606220
35345263800
725398672

After:

8
16
22
24
20

I pass everything else but the one I mentioned above.