Created
June 23, 2015 02:56
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JS convBase
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/** | |
* Convert base. | |
* | |
* @param string number | |
* @param string fromBase | |
* @param string toBase | |
* | |
* @return string|integer | |
*/ | |
var convBase = function(number, fromBase, toBase) { | |
if (fromBase == toBase) | |
return number; | |
var fromLen = fromBase.length; | |
var toLen = toBase.length; | |
var numberLen = number.length; | |
var retval = ''; | |
if (toBase === '0123456789') { | |
var retvalNum = big(0); | |
for (i = 1; i <= numberLen; i++) { | |
retvalNum = retvalNum.plus( | |
big(fromBase.indexOf(number.charAt(i-1))).times( | |
big(fromLen).pow(numberLen-i) | |
) | |
); | |
} | |
return retvalNum.toFixed(); | |
} | |
var base10; | |
if (fromBase !== '0123456789') { | |
base10 = convBase(number, fromBase, '0123456789'); | |
} else { | |
base10 = number; | |
} | |
if (base10 < toBase.length) | |
return toBase.charAt(base10); | |
while (base10 >= 1) { | |
retval = toBase.charAt(big(base10).mod(toLen))+retval; | |
base10 = big(base10).div(toLen); | |
} | |
return retval; | |
}; |
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http://php.net/manual/en/function.base-convert.php#106546
https://github.com/MikeMcl/big.js/