when I use Math.pow(9, 18) =150094635296999136
when I use web Calculator 9^18 = 150094635296999121 (http://web2.0calc.com/)
when I use Google calculator 9^18 = 1.50094635 × 10^17
why it is different ?
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Matt R. Wilson
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JavaUser
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2different because of precision. – Mitch Wheat Jun 02 '11 at 05:23
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web2.0calc.com and google calculator are showing same results but, in different notation. Google is displaying in **scientific** notation. Some precision is lost in scientific notation. – Sarwar Erfan Jun 02 '11 at 05:23
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See: http://stackoverflow.com/questions/5407298/am-i-going-crazy-on-is-math-pow-broken – Josh Lee Jun 02 '11 at 05:29
1 Answers
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At that range, the difference between successive double values is 32. 150094635296999121 is the correct answer as an integer, but that number cannot be exactly represented as a double.
You can use BigInteger to get the exact answer:
Math.pow(9, 18) == 150094635296999136
BigInteger.valueOf(9).pow(18) == 150094635296999121
Josh Lee
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