Wolfram Language & System 10.4 (2016)|Legacy Documentation

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gives the natural logarithm of z (logarithm to base ).

gives the logarithm to base b.


  • Log is a mathematical function, suitable for both symbolic and numerical manipulation.
  • Log gives exact rational number results when possible.
  • For certain special arguments, Log automatically evaluates to exact values.
  • Log can be evaluated to arbitrary numerical precision.
  • Log automatically threads over lists.
  • Log[z] has a branch cut discontinuity in the complex z plane running from to .
Introduced in 1988