
abs - modulus of a real or complex expression

Calling sequence:
abs(expr)

Parameter:

expr   --  expression

Overloading:

all

Summary:

abs returns the modulus of a real or complex expressions.  For expressions
of type DOM_EXPR the determination of the modulus of an expression can be
defined under the function attribute "abs" in the form of a procedure or
function. If the operator of expr has such an attribute then the procedure or
function under the entry of the attribute "abs" is called with the operands
of expr and the result is returned.

If expr is a real or complex number then the kernel function abs will be used
to determine its modulus.

>>  abs( -1.2 );

      1.2

>>  abs( -8/3 );

      8/3

>>  abs( 1+I );

       1/2
      2

>>  abs( PI*I );

      PI

>>  abs( a+a );

      2 abs(a)

