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Re: Strange log behavior?

by ikegami (Pope)
on Sep 07, 2013 at 16:42 UTC ( #1052826=note: print w/ replies, xml ) Need Help??


in reply to Strange log behavior?

>perl -E"say sprintf '%.20g', log (1000) / log (10)" 2.9999999999999996 >perl -E"say int( log (1000) / log (10) )" 2 >perl -E"say log (1000) / log (10) % 3" 2 >perl -E"say 2 % 3" 2

Always use a tolerance when comparing floating point numbers or converting them to integers.


Comment on Re: Strange log behavior?
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Re^2: Strange log behavior?
by Anonymous Monk on Sep 07, 2013 at 17:27 UTC
    What is the correct way to round the floating point number to 3?

      sprintf seems to do the right thing.

      perl -E ' say sprintf q{%.0f}, $_ for 2.99999, 2.49999, 3, -2.99999, -2.49999, 5279.8012;' 3 2 3 -3 -2 5280 $

      I hope this is helpful.

      Cheers,

      JohnGG

        Thanks, just what I needed.

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