Statistics
The Statistics channel generates statistical output data from source transducer or computed channel input data.
NOTE
Measurand and Units are inherited from the selected input channel. Description and Range values are initialized on selection of the input channel.
- Statistic: Select the desired statistical mode from the set of options provided. The statistical math equations are listed below.
- Percentile: For the Xth percentile mode, specify the X value as an integer between 0 and 100. The output is the value at the Xth percentile of the sample window. If necessary, an output value is interpolated between the input values that border the exact Xth percentile. Note that an X value of 0 returns the minimum input value and an X value of 100 returns the maximum input value.
- Window samples: Specify the number of input samples used to generate one output sample. This sets the size of the analysis window and also the associated output sample rate (i.e., the output sample rate is the input sample rate divided by this parameter). This can be any positive integer greater than one. The first output sample will have a time stamp of 0 in regard to elapsed run time. Because of this, the output data samples will appear to lead the input channel data samples when both are plotted against elapsed run time. A Time base shifter computed channel defined with a Lag of 1 sample can be used to change this if desired.

Following are the equations used to compute the statistical values where n is the specified number of window samples.
Mean |
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Standard deviation |
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RMS (root mean square) |
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Kurtosis |
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Skewness |
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