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sign -- sign (signum) function

Usage:

sign x
Inputs:
- x, a number,
Outputs:
- an integer or a complex number,

Description

When x is real, then this returns 1 if it is positive, -1 if it is negative, and 0 if it is zero.

i1 : sign 5

o1 = 1

i2 : sign (-3)

o2 = -1

i3 : sign 0

o3 = 0

If x is complex and nonzero, then this returns $x/|x|$.

i4 : sign(-7*ii)

o4 = -ii

o4 : CC (of precision 53)

See also

sign(LieElement) -- get the sign of a homogeneous element
sign(Permutation) -- computes the sign of a permutation

Ways to use sign:

sign(Constant)
sign(Number)

For the programmer

The object sign is a method function.

The source of this document is in Macaulay2Doc/functions/sign-doc.m2:30:0.