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Re: Histogram ignores 'bspec' (bin spec) ??

• To: mathgroup at smc.vnet.net
• Subject: [mg126755] Re: Histogram ignores 'bspec' (bin spec) ??
• From: "Chris Degnen" <degnen at cwgsy.net>
• Date: Tue, 5 Jun 2012 04:51:29 -0400 (EDT)
• Delivered-to: l-mathgroup@mail-archive0.wolfram.com
• References: <jqhr60$klr$1@smc.vnet.net>

The bin number specification is approximate, grouping to simple numbers.

The legacy version of Histogram had an option called ApproximateIntervals 
which would control "whether to adjust the interval boundaries to be simple 
numbers".  You can read this in the 'More information' section here:
 http://reference.wolfram.com/mathematica/Histograms/ref/Histogram.html

You can obtain a histogram with exactly 10 bins using the bin width 
specification, dx.

I.e. Histogram[foo, {(Max@foo - Min@foo)/(10 - 1)}]

So your code below would be:

SeedRandom[1];
foo = RandomVariate[NormalDistribution[0, 1], 1000];
{fmin, fmax} = #@foo & /@ {Min, Max};
baz = Table[Histogram[foo, {(fmax - fmin)/(k - 1)}], {k, 8, 15}]
1 == Length[DeleteDuplicates[baz]]



James Stein wrote:
>
> I would like to plot a histogram with a fixed number of bars, e.g. ten 
> bars.
> Consider this code:
>
> SeedRandom [ 1 ] ;
> foo = RandomVariate [ NormalDistribution [ 0, 1], 1000 ] ;
> baz = Table [ Histogram [ foo, k ], { k, 8, 15 } ] ;
> 1 == Length [ DeleteDuplicates [ baz ] ]
>
> The last line prints 'True', confirmed by visual inspection of baz which
> reveals eight identical histograms, each containing 13 bins. What do I 
> fail
> to understand here?
>
>