This is documentation for Mathematica 3, which was
based on an earlier version of the Wolfram Language.
 DirectedInfinity DirectedInfinity[ ] represents an infinite numerical quantity whose direction in the complex plane is unknown. DirectedInfinity[ z ] represents an infinite numerical quantity that is a positive real multiple of the complex number z. You can think of DirectedInfinity[ z ] as representing a point in the complex plane reached by starting at the origin and going an infinite distance in the direction of the point z. The following conversions are made: Certain arithmetic operations are performed on DirectedInfinity quantities. In OutputForm, DirectedInfinity[ z ] is printed in terms of Infinity, and DirectedInfinity[ ] is printed as ComplexInfinity. See the Mathematica book: Section 3.1.8. See also: Indeterminate. Further Examples The FullForm of Infinity shows that it has a direction. In[1]:= Out[1]//FullForm= Here is an indeterminate form. In[2]:= Infinity::indet: Indeterminate expression (-Infinity) + (Infinity) encountered. Out[2]= This can be thought of as infinity along the complex axis. In[3]:= Out[3]//FullForm=