Implement more compact syntax for permutations and combinations, or possibly a facility to suggest "proper" function symbols for ones users might try

[mathletedev]

Just a small feature request: Is it possible to have permutations/combinations in the evaluate() function? Something like 5 choose 3 or 5C3 would be nice. Thanks!

[vels10]

Can i able to solve this Issue?

[josdejong]

Yeah, so you would like to introduce two new operators to enter permutations/combinations in a more compact way. That would be nice indeed I'm not sure this is a broad enough use case to introduce two new operators though, but we can think this through at least.

What operator names would you suggest for both functions? It should be really clear from the names whether this is about permutations or combinations.

[m93a]

On calculators, combination and permutation numbers are typically written as nCr and nPr. How about adding these two functions as shorthands for combinations and permutations?

math.nCr(5,3) // 10
math.nPr(4,2) // 12

math.evaluate(`nCr(5, 3)`) // 10

[josdejong]

Yes that is right indeed, nCr and nPr. I would like to keep the amount of "duplicate" functions minimal though, try to have only one way to do things. To prevent people from wondering "is nCr the same as combinations or is it doing different things?".

Maybe we could introduce a solution that gives you an error message with a hint when you enter "nCr": "You used 'nCr' you mean 'combinations'?", having defined a list with aliases and maybe also common typos in function names. Or maybe it's just ok like it is now and we should not over-engineer this 😁 .

[gwhitney]

Since this seems to be an open-ended idea (possibly add a facility for "function suggestions"), re-titling and moving to Discussions.

[gwhitney]

See also #1764, where essentially the same idea of a "hinting system" came up.