How to compute the dot product?

Posted by WizardOfOdds on Stack Overflow See other posts from Stack Overflow or by WizardOfOdds
Published on 2010-03-28T13:17:43Z Indexed on 2010/03/28 13:43 UTC
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math

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cross-product

I have the following piece of pseudo-C/Java/C# code:

int a[]= { 30, 20 };
int b[] = { 40, 50 };
int c[] = {12, 12};

How do I compute the sign of the dot-product AB . AC?

I'm only interested in the sign, so I have:

boolean signABxAC = ?

Now concretely what do I write to get the sign of the dot-product AB . AC?

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