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based on an earlier version of the Wolfram Language.
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gives the exponential integral function Ei(z).
  • Mathematical function, suitable for both symbolic and numerical manipulation.
  • , where the principal value of the integral is taken.
  • ExpIntegralEi[z] has a branch cut discontinuity in the complex z plane running from - to 0.
  • For certain special arguments, ExpIntegralEi automatically evaluates to exact values.
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