discrete mathematics - Calculating the sign of a NxN determinant -


is there more efficient way determine sign (negative or positive or zero) of determinant calculating full value of determinant , comparing zero?

there methods, can approximate determinat of integer matrix faster, computing exact value. these methods used compute sign, since there great probability of correct result. see this paper more details.

however afaik there no exact method of computing sign of determinant faster computing value itself.


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