zcross

Compute zero crossing density.

Usage

zcross(x {type {, sr {, xth}}})

x

data vector (signal)

type

selects the type of result; 0 ≤ type ≤ 3 (default=0)

sr

sampling rate in Hz (default=1)

xth

threshold value (default=0); if xth is a value greater than 0, fluctuations of the function in the range -xth < x[i] < xth are ignored

Result

The function counts the number of zero crossings z of the function x[i] = f(i). The returned result is a scalar depending on z and the argument type.

type	description	result
0	the number of zero crossing	z
1	the zero crossing density (number of zero crossings / second)	d = z / (ncol(x) * sr)
2	the average zero crossing frequenzy (in Hz)	f = d / 2
3	the average zero crossing periode length (in seconds)	t = 1 / f = 2 / d

See also

f0ac

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