@NM_10165576 wrote:
Could you please give me brief explanation
Sure. The function generate takes a single argument, n.
The matrix L stores each permutation of n, one per row.
The outer k-loop runs over each value in the first row of n; The 1st and k-th values of n exchange places at the start of the loop. This has the effect of leaving the rest of n in the correct lexicographical order. (the first swap when k = 0 leaves n unchanged but it's not worth the brain clock cycles trying to do anything fancy to make it more efficient)
The inner i-loop iterates over each permutation of n in its k-th state. m is the permutation counter and its binary representation as a vector allow generate to select which of the n elements to copy to matrix L and which to set to zero. (Note: If a Mathcad matrix (or any array) element isn't explicitly set to some value, it defaults to zero. If I'd used an "if" programming statement instead of an "if" function, I could have used the behaviours, but the if function allows you to set a default value other than zero should you so wish).
Rinse and repeat until generate has run its course.
I'm sure there are multiple better ways to solve the problem, but that's the method that first occurred to me.
Stuart
