Histogram Peaks; Binning And Measurement Accuracy - LeCroy SDA Operator's Manual

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hist top histogram top or rightmost of two largest peaks
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max populate population of most populated bin in histogram
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mode data value of most populated bin in histogram
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percentile data value in histogram for which specified `x'% of population is smaller
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peaks number of peaks in histogram
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pop @ x population of bin for specified horizontal coordinate
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range difference between highest and lowest data values
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total pop total population in histogram
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x at peak x-axis position of specified largest peak

Histogram Peaks

Because the shape of histogram distributions is particularly interesting, additional parameter
measurements are available for analyzing these distributions. They are generally centered
around one of several peak value bins, known, with its associated bins, as a histogram peak.
Example: In the following figure, a histogram of the voltage value of a five-volt amplitude square
wave is centered on two peak value bins: 0 V and 5 V. The adjacent bins signify variation due to
noise. The graph of the centered bins shows both as peaks.
Determining such peaks is very useful because they indicate dominant values of a signal.
However, signal noise and the use of a high number of bins relative to the number of parameter
values acquired, can give a jagged and spiky histogram, making meaningful peaks hard to
distinguish. The scope analyzes histogram data to identify peaks from background noise and
histogram definition artifacts such as small gaps, which are due to very narrow bins.

Binning and Measurement Accuracy

Histogram bins represent a sub-range of waveform parameter values, or events. The events
represented by a bin may have a value anywhere within its sub-range. However, parameter
measurements of the histogram itself, such as average, assume that all events in a bin have a
single value. The scope uses the center value of each bin's sub-range in all its calculations. The
greater the number of bins used to subdivide a histogram's range, the less the potential deviation
between actual event values and those values assumed in histogram parameter calculations.
SDA-OM-E Rev H
SDA Operator's Manual
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