The Numbers Magic (Amsterdam Node Meetup Presentation)

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Numbers the Magic

Transcript of The Numbers Magic (Amsterdam Node Meetup Presentation)

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Numbersthe

Magic

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@lucamaraschi

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Once upon the time…

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Numbers are not perfect

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in JS“primitive value corresponding to a double-precision 64-bit binary format IEEE 754 value”

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64bits

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Sign

Sign

ExponentMantissa

+

+

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Sign

exponent11bit

s

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Sign

exponentposition of the floating point!

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Sign

mantissa52bit

s

1hidden

bit

+

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so 0.1 is not really 0.1

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Fractionsbuild of the inverse power of 2

only 52 bits of mantissaand

fix size of 64bitsand

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53 bits of exponentcan only represent every second integer

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Future

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DEC64Coefficient

* 10^Exponent=

by Douglas Crockford

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DEC64Coefficient Exponent

8 bits56 bits

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Physicians accept the uncertainty of the

measurementWalter Lewin

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we are hiring. icemobile.com/jobs

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icemobile.com/blog /company/icemobile

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IceMobileAmsterdam @icemobile@icemobile

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Adding emotion to transactional loyalty