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Matrix multiplication vs component-wise multiplication in W|A?


Hi, I have a question about a rather strange behavior of Wolfram Alpha. Let us suppose A+B=C are matrices.

1) If you input C^2, you get an actual matrix multiplication. (example: {{1,2},{3,4}}^2)

2) However, if you input (A+B)^2, wolfram alpha evaluates it all component-wise. (example: ({{0,0},{0,0}}+{{1,2},{3,4}})^2 )

This wouldn't be as confusing if it wasn't for the way how wolfram alpha depicts this: input: ({{0,0},{0,0}}+{{1,2},{3,4}})^2

If I enter explicitely that I want the matrix power (input: MatrixPower[{{1,0},{0,0}}+{{1,2},{3,4}},2]), the result is right (the matrix power of the addition), but the depiction is even more confusing: input: MatrixPower[{{0,0},{0,0}}+{{1,2},{3,4}},2]

Is this a bug or is there some sensible reason for this behavior?

POSTED BY: Ondrej Draganov
7 days ago

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