8
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Bug introduced in 8.0 and fixed in 10.0.0

Just try this example:

lst = {0, 1, 1, Sqrt[2], Sqrt[5], 2 Sqrt[2], 2, Sqrt[13], Sqrt[5], Sqrt[6], Sqrt[11], 
       Sqrt[14], Sqrt[11], Sqrt[10], 3 Sqrt[2], Sqrt[17], Sqrt[13], 2 Sqrt[5], Sqrt[29], 
       2 Sqrt[2]};

ex1 = BinCounts[lst, {Range[0, 18]}]
ex2 = BinCounts[lst, {Range[0, 19]}]
ex3 = BinCounts[N@lst, {Range[0, 18]}]

{1, 2, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}
{1, 3, 6, 6, 3, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}
{1, 3, 6, 6, 3, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}

Seems that BinCounts failed to notice the irrational numbers in ex1:

Select[lst, IntegerQ]

(* This result is consistent with ex1. *)
{0, 1, 1, 2}

Is it a bug? I'm using Mathematica 8.0.4, Windows Vista 32bit.

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  • 1
    $\begingroup$ Same result in 9.0.1. Odd behavior indeed; seems hard to justify it as anything other than a bug... $\endgroup$
    – Oleksandr R.
    May 20, 2014 at 10:25
  • $\begingroup$ Try BinCounts[lst + $MachineEpsilon, {Range[0, 18]}]... looks bug-like to me. You can use N, or Length /@ BinLists[lst, {Range[0, 18]}] as work-around. $\endgroup$
    – ciao
    May 20, 2014 at 10:26
  • $\begingroup$ same result in OSX v9.0.1 $\endgroup$
    – gpap
    May 20, 2014 at 10:36
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    $\begingroup$ But HistogramList[lst, {Range[0, 18]}] works ok. $\endgroup$
    – b.gates.you.know.what
    May 20, 2014 at 10:37
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    $\begingroup$ minimal example: BinCounts[{0, 3, Sqrt[2]}, {Range[1, 2]}] -> {0} $\endgroup$
    – george2079
    May 20, 2014 at 19:58

1 Answer 1

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3
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This bug has been fixed in v10.0 (Tested on Wolfram Programming Cloud):

enter image description here

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1
  • $\begingroup$ In MMA V10 desktop version it's ok too. $\endgroup$
    – Murta
    Jul 15, 2014 at 11:14

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