Re: While loop with addition goes weird (binary float rounding error)

Because 0.01 = 1/(2*2*5*5) is a decimal not a binary fraction.

That means it can't be expressed without rounding error as a binary floating point number.(5 and 2 are different primes), pretty much like how you can't express 1/3 as a finite decimal floating point number without.

Cheers Rolf
_{(addicted to the Perl Programming Language and ☆☆☆☆ :)

Wikisyntax for the Monastery}

Comment on Re: While loop with addition goes weird (binary float rounding error)

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Re^2: While loop with addition goes weird (binary float rounding error) by chiel (Initiate) on Apr 08, 2018 at 13:52 UTC
Thanks for your reply. But to me, your answer is as difficult to understand as my problem ;) Can you explain it more simplistic? Maybe with example on how to do it? I'm just trying to add numbers here.	[reply]
Re^3: While loop with addition goes weird (binary float rounding error) by afoken (Chancellor) on Apr 08, 2018 at 14:24 UTC
Don't be so lazy, follow the two links posted by LanX++. Alexander -- Today I will gladly share my knowledge and experience, for there are no sweeter words than "I told you so". ;-)	[reply]
Re^3: While loop with addition goes weird (binary float rounding error) by BillKSmith (Monsignor) on Apr 09, 2018 at 04:00 UTC
We can almost always ignore floating-point errors and round our results with printf. Unfortunately there is no "simplistic" way to recognize the rare cases where this is a bad idea (Or what to do about it if you really have one). The documents already cited are not easy to read! Be assured that they to not require knowledge of any math beyond elementary algabra - only a commitment to learn. Bill	[reply]
Re^4: While loop with addition goes weird (binary float rounding error) by Anonymous Monk on Apr 13, 2018 at 19:50 UTC
These might be more digestible (not 67 pages article) :) Is this odd behavior a floating point problem?, What Every Programmer Should Know About Floating-Point Arithmetic or Why don’t my numbers add up?	[reply]
Re^5: While loop with addition goes weird (binary float rounding error) by BillKSmith (Monsignor) on Apr 14, 2018 at 13:08 UTC