[Pdx-pm] Unexpected math result
chromatic at wgz.org
Wed Dec 21 11:34:23 PST 2011
On Wednesday, December 21, 2011 at 11:31 AM, Michael R wrote:
> Silly me would expect something like 0 to be printed. Why the
> 2.16840434497101e-18? (OK, round it off and you have 0, but ....)
This is a feature of how computers usually represent floating point numbers.
perlfaq4 points to David Goldberg's "What Every Computer Scientist Should Know
About Floating-Point Arithmetic" at:
The short of it is that you can't represent certain fractional components
precisely with a powers-of-two representation.
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