Secret sharing over reals - Difficulty with Computer implementation
Recall the definition of a $(k,n)$-threshold secret sharing scheme is that any group of at least $k$ players (out of $n$ total players) can recover the secret given their shares.  The naive method for constructing a threshold scheme out of a non-threshold scheme (which was recommended in your previous question's answer) is giving every possible $k$-combination of the $n$ players a fresh $(k,k)$ sharing of the secret.  (I'll note that this is only practical for small values of $n$.)

It seems that you are stuck on the question of how to enumerate all of the possible combinations.  A good reference is this comprehensive answer on Stack Overflow, which mentions several algorithms.

Here is a quick Python script that will calculate all of the combinations for $k=3, n=5$:

import itertools

players = {1, 2, 3, 4, 5}
k = 3
for subset in itertools.combinations(players, k):
    print(subset)


With the resultant subsets:

(1, 2, 3)
(1, 2, 4)
(1, 2, 5)
(1, 3, 4)
(1, 3, 5)
(1, 4, 5)
(2, 3, 4)
(2, 3, 5)
(2, 4, 5)
(3, 4, 5)


This is of course a general algorithm that will work for any values of $k$ and any set of players.