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Sign

FilledSmallSquare Sign[x] gives -1, 0 or 1 depending on whether x is negative, zero, or positive.

FilledSmallSquare For non-zero complex numbers z, Sign[z] is defined as z/Abs[z].

FilledSmallSquare Sign tries simple transformations in trying to determine the sign of symbolic expressions.

FilledSmallSquare For exact numeric quantities, Sign internally uses numerical approximations to establish its result. This process can be affected by the setting of the global variable $MaxExtraPrecision.

FilledSmallSquare See Section 3.2.2.

FilledSmallSquare See also: Abs, UnitStep, Positive, Negative, NonNegative, Greater, Simplify, Assumptions.

FilledSmallSquare New in Version 1; modified in 3.

Further Examples