[R] cycle in a directed graph

[Jeff Newmiller]

Lacking any reference to R, this message is off-topic on this mailing list. You might try math.stackexchange.com.
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Sent from my phone. Please excuse my brevity.

On May 3, 2015 8:36:29 AM PDT, Dany <daniela_scida at brown.edu> wrote:
>Hi I saw the answer: 
>
>�If the graph has n nodes and is represented by an adjacency matrix,
>you can square the matrix (log_2 n)+1 times. Then you can multiply the
>matrix element-wise by its transpose. �
>
>I�m a PhD student working on my research and I need to check for cycles
>in a directed graph to make sure it is a DAG. The answer given is
>extremely useful but I need the theorem statement, or a reference. Do
>you have a book where this is stated or a paper?
>
>Thanks!
>
>Daniela.
>	[[alternative HTML version deleted]]
>
>
>
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