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A query to the selected Intensity object.
the standard deviation (in dB) of the intensity values of the frames within a specified time domain.
The standard deviation between the times t1 and t2 is defined as
√ {1/(t2 - t1) ∫t1t2 dt (x(t) - μ)2} |
where x(t) is the intensity (in dB) as a function of time, and μ its mean. For our discrete Intensity object, the standard deviation is approximated by
√ {1/(n-1) ∑i=m..m+n-1 (xi - μ)2} |
where n is the number of frames between t1 and t2. Note the "minus 1".
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