Multivariate Lambda Function In Python That Scales With Number Of Input Variables Received

The following toy function ordinarily takes two input variables: f = lambda u1, u2 : (u1*u2)*(u1**2+u2**2) but can scale beyond the bivariate case to higher dimensions: if dim ==

Solution 1:

The lambda syntax supports the same parameter list syntax as the def syntax, including variadic positional and keyword argument.

f = lambda *us: math.prod(us) * sum(u**2for u in us)

If the *us are not invariant when multiplied by 1 or added to 0, the * and + operations can be applied across elements via reduce:

from functools import reduce
import operator

f = lambda *us: reduce(operator.mul, us) * reduce(operator.add, (u**2for u in us))