Sign function
Mathematical function returning -1, 0 or 1 / From Wikipedia, the free encyclopedia
"Sgn" redirects here. For other uses, see SGN (disambiguation).
Not to be confused with Sign relation or Sine function.
In mathematics, the sign function or signum function (from signum, Latin for "sign") is a function that has the value −1, +1 or 0 according to whether the sign of a given real number is positive or negative, or the given number is itself zero. In mathematical notation the sign function is often represented as or .[1]