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I'm having trouble calculating roots of rather large numbers using bc_math, example:

 - pow(2, 2)        // 4, power correct
 - pow(4, 0.5)      // 2, square root correct
 - bcpow(2, 2)      // 4, power correct
 - bcpow(4, 0.5)        // 1, square root INCORRECT

Does anybody knows how I can circumvent this? gmp_pow() also doesn't work.

Alix Axel
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    For anyone searching a GMP solution, I've provided one here: http://stackoverflow.com/q/21953495/603003 – ComFreek Feb 22 '14 at 11:22

1 Answers1

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I'm not a PHP programmer but looking at the manual it says you have to pass them in as strings i.e.

bcpow( '4', '0.5' )

Does that help?

Edit: The user contributed notes in the manual page confirm that it doesn't support non-integer exponents.

I did come across this discussion of a PHP N-th root algorithm after a quick search so perhaps that's what you require.

Troubadour
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