You are correct: in the ordinary way of throwing dice and adding their results, 2 dice yields a linear distribution, peaking in the middle.What I programmed was different: averaging the results of 2 random floats yields what appears to be a parabolic distribution, peaking in the middle of the range.

At this point, anybody reading who did well in probability and statistics is having a hearty laugh. Clearly it doesn't correspond well to dice, although it does give a practically useful probability distribution over a selected range (using normals, you can't be sure your results will be in your desired range).

Inspired to produce a more bell-like result and to more accurately simulate real-life dice-throwing, I came up with a new sub. The fewer sides the dice have, the more you can throw and sum to get a result in the desired range, so I made two-sided dice (which are usually called coins): 

sub flip_coins {
  my ($low_end, $range) = @_;
  my $result = 0;
  $result += int(rand 2) for (2..$range);
  $low_end + $result;
}

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Results at the extreme ends of the range are very sparse, so I like the distribution of my original better.
The PerlMonk tr/// Advocate

In reply to Re^2: Fractional dice (more not fewer) by Roy Johnson
in thread Fractional dice by Roy Johnson

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