1
$\begingroup$

I have a list of length twelve:

p = {t[1, 1], t[1, 2], t[1, 3], t[1, 4], t[2, 2], t[2, 3], t[2, 4], 
 t[1, 5], t[3, 3], t[3, 4], t[1, 6], t[4, 4]}

and a set of inequalities

U = t[1, 1] > 0 && -t[1, 2]^2 + t[1, 1] t[2, 2] > 
  0 && -t[1, 3]^2 t[2, 2] + 2 t[1, 2] t[1, 3] t[2, 3] - 
   t[1, 1] t[2, 3]^2 - t[1, 2]^2 t[3, 3] + t[1, 1] t[2, 2] t[3, 3] > 
  0 && t[1, 4]^2 t[2, 3]^2 - 2 t[1, 3] t[1, 4] t[2, 3] t[2, 4] + 
   t[1, 3]^2 t[2, 4]^2 - t[1, 4]^2 t[2, 2] t[3, 3] + 
   2 t[1, 2] t[1, 4] t[2, 4] t[3, 3] - t[1, 1] t[2, 4]^2 t[3, 3] + 
   2 t[1, 3] t[1, 4] t[2, 2] t[3, 4] - 
   2 t[1, 2] t[1, 4] t[2, 3] t[3, 4] - 
   2 t[1, 2] t[1, 3] t[2, 4] t[3, 4] + 
   2 t[1, 1] t[2, 3] t[2, 4] t[3, 4] + t[1, 2]^2 t[3, 4]^2 - 
   t[1, 1] t[2, 2] t[3, 4]^2 - t[1, 3]^2 t[2, 2] t[4, 4] + 
   2 t[1, 2] t[1, 3] t[2, 3] t[4, 4] - t[1, 1] t[2, 3]^2 t[4, 4] - 
   t[1, 2]^2 t[3, 3] t[4, 4] + t[1, 1] t[2, 2] t[3, 3] t[4, 4] > 0

involving the members of the list.

I--undoubtedly foolhardily (because of the computational demands involved)--want to try repeatedly invoking the command

GenericCylindricalDecomposition[U, q],

where q is a random permutation (one of the 12!=479,001,600 possible) of the members of p (to find which--if successful, for further integration purposes--has the lowest LeafCount).

The immediate question at hand, though, is how I can generate such a random permutation q without having to explicitly create such an immensely long list from which to randomly choose members.

Improve this question
$\endgroup$
2
  • 2
    $\begingroup$ I am not sure whether I fully understand the question, but are you perhaps looking for q = RandomSample[p]? $\endgroup$
    – Domen
    Jul 10, 2021 at 20:03
  • $\begingroup$ RandomSample[p] accomplishes what I sought. Thanks, Domen! $\endgroup$
    – Paul B. Slater
    Jul 10, 2021 at 20:16

0

Reset to default