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Arg

  • Arg[ z ] gives the argument of the complex number z.
  • Mathematical function (see Section A.3.10).
  • Arg[ z ] is left unevaluated if z is not a numeric quantity.
  • Arg[ z ] gives the phase angle of z in radians.
  • The result from Arg[ z ] is always between and .
  • Arg[ z ] has a branch cut discontinuity in the complex z plane running from to .
  • See the Mathematica book: Section 1.1.5Section 3.2.2.
  • See also: ArcTan, Sign.

    Further Examples

    The argument of a complex number z gives the angle that the line from to z makes with the positive real axis.

    In[1]:=

    Out[1]=

    This gives the arguments of the units in the complex plane.

    In[2]:=

    Out[2]=