29 lines
880 B
ReStructuredText
29 lines
880 B
ReStructuredText
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.. _cumulative_histogram:
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Making a cumulative histogram
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=============================
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Overview
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--------
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A cumulative histogram is a histogram in which each bin stores the count / frequency of itself
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as well as all the bins with keys 'smaller' than the particular bin.
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As such, a notion of ordering among its keys should be existant in the histogram.
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The GIL histogram class has the ability to convert itself into its cumulative version.
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Since the container needs to first get an ordering
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over the keys a key sorting takes place before calculating the cumulative histogram.
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Example:
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.. code-block:: cpp
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histogram<int, float> h;
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/*
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Fill histogram ...
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*/
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auto h1 = cumulative_histogram(h);
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Tip: *In case you need to store the cumulative histogram elsewhere, consider creating a copy of the histogram
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and then call the function*.
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