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A comment on GCC Non-bugs. Parent comment

Re:GCC Non-bugs by dietrichepp on Monday March 02, 2015 @12:52AM (#9130497)
The result of the computation 1/3 in JS results in a number which is terminating, but that number is not 1/3. Open up your console and type 1/3+1/3+1/3... 1, as expected. Then type 1-1/3-1/3-1/3... I get about 1e-16, which is not 0.

The statement that "1/3 is terminating" is not true in binary, it is not true in decimal, and the only reason that you sometimes get the expected results is that sometimes the rounding errors will cancel out.

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Re:GCC Non-bugs by shortstuffsushi on Monday March 02, 2015 @11:59AM (#9132854)
I realize that 1/3 is not terminating in decimal, what I meant was that in JS, it seemed to end neatly after x decimal places, which I found interesting. I hadn't tried the operation you mentioned until you posted that, the results are even more bizarre to me. Seems I need to spend some time relearning floating point math to better understand what I'm seeing.
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Re:GCC Non-bugs by valleyer on Monday March 02, 2015 @02:52AM (#9130796)
So you're telling me we should use base 3.
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Re:GCC Non-bugs by jakobegger on Monday March 02, 2015 @03:29AM (#9130909)
Well then 0.5 would be non-terminating...
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