Group Abstract Group Abstract

Message Boards Message Boards

Multinomial equations for factoring a sum of equal grade exterior products

David J M Park Jr
Posted 6 years ago
POSTED BY: David J M Park Jr
4 Replies
Sort By:

Is there some reason not to use FindInstance from the outset?

FindInstance[canonicalEquations == 0, 
 Variables[canonicalEquations]]

(* Out[298]= {{a[1, 1] -> -1, a[1, 2] -> 5, a[1, 3] -> 11/4, 
  a[1, 4] -> 53/4, a[2, 1] -> -1, a[2, 2] -> 1, a[2, 3] -> 7/4, 
  a[2, 4] -> 41/4}} *)
POSTED BY: Daniel Lichtblau

Many thanks Daniel, that works pretty well and is simpler. Trying to factor a 5-form in 7-dimensional space using Solve I aborted the calculation after 15 minutes. Using FindInstance took 6 seconds. A significant improvement!
POSTED BY: David J M Park Jr

using FindMinimum with an objective function of 0 and the canonicalEquations as constraints would give you a numerical solution to your equations.

POSTED BY: Frank Kampas

Thank you Frank. This method is somewhat problematic. It sometimes gives a solution but other times doesn't ( saying possible infeasibility detected) when I know there is a solution because the equations were generated from a factored case that was then expanded to give the input.

Also FindMinimum gives Real answers while Solve with give Integer or Rational answers with Integer input.
POSTED BY: David J M Park Jr
Reply to this discussion
Community posts can be styled and formatted using the Markdown syntax.
Tag limit exceeded
Note: Only the first five people you tag will receive an email notification; the other tagged names will appear as links to their profiles.
Reply Preview
Attachments
Remove
or Discard