Normalized Smith-Waterman Formula

Question

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I found the following formula for normalizing Smith-Waterman scores, I know that p1 and p2 refer to first and second proteins, but I do not understand what SW(p1,p2) refers to. Can somebody please explain?

Answer 1

[Jean-Karim Heriche]

Hard to tell without context but my guess is that SW stands for Smith-Waterman so you normalize the score by the product of the square roots of the score of each protein aligned to itself.