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Ln(x) algorithm

  1. Aug 5, 2003 #1
    I was fiddling around with C++ and iterations and I found an algorithm for computing ln(x).

    n = any number, the higher, the better the approximation
    ln_x = 0;
    divisor = 10^n;

    while ( divisor <= x*10^n ) // Where x is the ln(x) you want to find.

    ln_x += 1 / divisor;


    What it does is add all integer fractions from 1/10^n to 1/x*10^(n+1).
  2. jcsd
  3. Aug 5, 2003 #2


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    Staff Emeritus
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    Gold Member

    You've discovered the fact that [inte](1/x) dx is ln(x). Congratulations!

    - Warren
  4. Aug 5, 2003 #3
    Thanks :)
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