identify the type of histograms

I have several histograms, how can I identify histograms like 1? I have read about hilbert function, but I can't understand how implement this.

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[Ryan]

So given a set of histograms, are you trying to identify those which match histogram 1?

[Walter Roberson]

It is not obvious to me that _any_ of them are histograms...

[the cyclist]

Alex, it seems to me that you should spend significantly more effort in explaining what it is you are trying to do. Sometimes a sentence or two just isn't enough for us.