When running
console.log(parseInt("9658921879781125"))9658921879781124, which is less than the original value.
Why is this the case?
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NikxDa
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1http://2ality.com/2012/07/large-integers.html – Harigovind R Dec 14 '17 at 10:42
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but it is able to convert 9658921879781126 properly – Manoj Sureddi Dec 14 '17 at 10:43
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1See G. Petrioli's answer. It's unsafe, it doesn't mean it will fail every time. – NikxDa Dec 14 '17 at 10:43
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Yea I am now taking a substring of the biginteger and comparing it so that it would be less that the safe limit. Thanks! – Manoj Sureddi Dec 14 '17 at 10:48
1 Answers
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That would be because
9658921879781125 > Number.MAX_SAFE_INTEGER // true
So it is unsafe to try to work with numbers greater than Number.MAX_SAFE_INTEGER
The
MAX_SAFE_INTEGERconstant has a value of9007199254740991(9,007,199,254,740,991 or ~9 quadrillion). The reasoning behind that number is that JavaScript uses double-precision floating-point format numbers as specified in IEEE 754 and can only safely represent numbers between -(253 - 1) and 253 - 1.Safe in this context refers to the ability to represent integers exactly and to correctly compare them.
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