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The math library provides a number of useful math functions as well as special functions for plane-angle conversions, digests, trigonometry, and great-circle calculations. More are added as needed. 

General

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random

random(<num>) - generate a random number. The value is between 0 and the number given as an argument.

  r = math:random(999)

The given example will return random digits between 0 and 3 inclusive:

rule random_example {
  select when pageview ".*"
  pre{  
    r = math:random(3);
  }
  {
    notify("Random Number","r = #{r}") with sticky = true;
  }
}

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Functionsexponent

exp(<num>) - return e (natural logrithm) raised to the <num>th power

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