3
$\begingroup$
R[a_, b_] := FullSimplify[ KroneckerDelta[a, b] KroneckerDelta[a, b]]
R[a, b]
(* KroneckerDelta[a, b]^2 *)

Should the the full simplified answer not be just KroneckerDelta[a, b] due to idempotence?

$\endgroup$
1
  • $\begingroup$ Failure to simplify isn't a bug - so I'd suggest changing the title of the question. $\endgroup$
    – Jens
    Dec 31, 2016 at 4:21

1 Answer 1

8
$\begingroup$

Use PiecewiseExpand

R[a_, b_] := KroneckerDelta[a, b] KroneckerDelta[a, b] // PiecewiseExpand

R[a, b]

enter image description here

R[a_, b_] := Product[KroneckerDelta[a, b] , {n, 5}] // PiecewiseExpand

R[a, b]

enter image description here

R[a_, b_] := 
 Product[KroneckerDelta[a, b] , {n, m}] // PiecewiseExpand[#, m > 1] &

R[a, b]

enter image description here

$\endgroup$

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.