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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=