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ExpIntegralEi

  • ExpIntegralEi[ z ] gives the exponential integral function .
  • Mathematical function (see Section A.3.10).
  • , where the principal value of the integral is taken.
  • ExpIntegralEi[ z ] has a branch cut discontinuity in the complex z plane running from to .
  • See the Mathematica book: Section 3.2.10.
  • See also: ExpIntegralE, Erf, LogIntegral, SinIntegral, CosIntegral.

    Further Examples

    This is the derivative.

    In[1]:=

    Out[1]=

    This is the integral.

    In[2]:=

    Out[2]=

    This is a series expansion around .

    In[3]:=

    Out[3]=