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in reply to Re^3: Split range 0 to M into N non-overlapping (roughly equal) ranges.
in thread Split range 0 to M into N non-overlapping (roughly equal) ranges.

I'm seeing the same numbers as you. But what is your output for: ranges -M=20 -N=3 ?

I get: 0-6, 7-13, 14-20.

I expect the last index to be 19.

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Re^5: Split range 0 to M into N non-overlapping (roughly equal) ranges.
by BrowserUk (Patriarch) on Mar 13, 2011 at 07:13 UTC
    I expect the last index to be 19.

    Why? The range is 0 .. 20 inclusive: 

    [ 6:17:58.02] C:\test>ranges -M=20 -N=3
 0 : from       0 to       6 (      7)
 1 : from       7 to      13 (      7)
 2 : from      14 to      20 (      7)
========================================
                                   21

[ 7:10:34.53] C:\test>ranges -M=20 -N=2
 0 : from       0 to       9 (     10)
 1 : from      10 to      20 (     11)
========================================
                                   21

[ 7:11:36.69] C:\test>ranges -M=20 -N=1
 0 : from       0 to      20 (     21)
========================================
                                   21

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[d/l]
      But this isn't 0 .. 14 inclusive:
      [ 6:16:11.35] C:\test>ranges -M=14 -N=11
 0 : from       0 to       0 (      1)
 1 : from       1 to       1 (      1)
 2 : from       2 to       3 (      2)
 3 : from       4 to       4 (      1)
 4 : from       5 to       5 (      1)
 5 : from       6 to       7 (      2)
 6 : from       8 to       8 (      1)
 7 : from       9 to       9 (      1)
 8 : from      10 to      11 (      2)
 9 : from      12 to      12 (      1)
10 : from      13 to      13 (      1)
========================================
                                   14

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      Based on your previous results, I expect non-inclusive every time. If my expectation is wrong, then why is the result above non-inclusive (i.e. does not end with index 14)?

      (I'm not adamant on my expectation of non-inclusiveness. I just expect consistent behavior. :-)
[reply]
[d/l]

        Ah! Now I see the problem. (Phraseology lacking).

        Preliminary response:

        my $STEP = ( $M + 1.5 ) / $N;

        [download]
        Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
        "Science is about questioning the status quo. Questioning authority".
        In the absence of evidence, opinion is indistinguishable from prejudice.
[reply]
[d/l]

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