Abs[z] gives the absolute value of the real or complex number z.
For complex numbers , Abs[z] gives the modulus .
Abs[z] is left unevaluated if z is not a numeric quantity.
See Section 1.1.3, Section 1.1.5, Section 3.2.2 and Section 3.2.2.
See also: Re, Im, Arg, Mod, ComplexExpand, Norm.
New in Version 1.