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> It does that for all floating point values - always to 15 decimal digits (unless perl's nvtype is other than "double") and always for a dubious reason.

The mantissa of a double has 52 bits°, you need 50 bits to encode 15 decimal digits ( 2**10 =1024, so rule of thumb 10 bits for 3 decimals)

So the last two bits are used for error correction, since they don't suffice to encode another decimal digit.

Is it a good solution? Well I'd say appropriate for the era and not "for a dubious reason".

Are there better approaches? Sure, but they are harder to implement and would have been quite slow back in the days.

From my experience, >95% of the problems arise from calculating with currencies and the solution is obvious, calculate with integer cents and move the point only for output.

Cheers Rolf
(addicted to the Perl Programming Language :)
Wikisyntax for the Monastery

°) WP actually says 53 by using a spare bit redundancy , but tl;dr and this still fails to encode 16 decimals.


In reply to Re^2: int() function by LanX
in thread int() function by geoperl

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