Logarithm Algorithm

Question

I need to evaluate a logarithm of any base, it does not matter, to some precision. Is there an algorithm for this? I program in Java, so I\'m fine with Java code.

Ho

Answer 1

Use this identity:

log_b(n) = log_e(n) / log_e(b)

Where log can be a logarithm function in any base, n is the number and b is the base. For example, in Java this will find the base-2 logarithm of 256:

Math.log(256) / Math.log(2)
=> 8.0

Math.log() uses base e, by the way. And there's also Math.log10(), which uses base 10.