I need to do the following:
Transpose[A.(B+C)]=Transpose[B].Transpose[A]+Transpose[C].Transpose[A]
How should I do this in mathematica? So far mathematica does not distribute the operation. Thank you!
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$\begingroup$ The NCAlgebra package might be able to do this. $\endgroup$– SzabolcsJul 21, 2015 at 18:31
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10
Update: it seems this only works in 10.1 and later, but not in 10.0.
This works:
Assuming[(a | b | c) ∈ Matrices[{d, d}], TensorExpand@Transpose[a.(b + c)]]
(* Transpose[b, {2, 1}].Transpose[a, {2, 1}] + Transpose[c, {2, 1}].Transpose[a, {2, 1}] *)
We needed to tell Mathematica that a, b and c are square matrices and use TensorExpand.
Check here: Symbolic tensors.
answered Jul 21, 2015 at 18:33
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$\begingroup$ @Szabolcs I'm sorry but doing what you said gives in Mathematica 10.0:
Transpose[b + c, {2, 1}].Transpose[a, {2, 1}]which is not what I want. Suggestions? $\endgroup$ Jul 21, 2015 at 19:05 -
1$\begingroup$ Yes there was a bug in 10.0 that prevented this from working. It is fixed in 10.1 and later versions. $\endgroup$– Stefan RJul 21, 2015 at 19:48