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matrix - Taking the product of a list of matrices



Suppose I create a list of matrices:


data = Table[RandomInteger[5, {2, 2}], 5]

Which produces:


{{{0, 5}, {2, 1}}, {{5, 2}, {2, 1}}, {{4, 4}, {0, 1}}, {{5, 3}, {2, 

   5}}, {{2, 0}, {5, 0}}}

How can I quickly take the product of these five matrices?



Answer



Dot@@data should do what you're looking for. It replaces the main Head, List, with Dot, which just multiplies all of the matrices—which used to comprise the List data—together.


data = Table[RandomInteger[5, {2, 2}], 5];

MatrixForm /@ data

enter image description here



Dot @@ data // MatrixForm

enter image description here


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