1. Syntax
1.1. zplane(z,p)
1.1.1. Plot the zeros defined in vector column z and the poles specified in vector column p
1.2. zplane(b,a)
1.2.1. Roots are used to locate the transfer function zeros and poles represented by the numerator coefficients b and the denominator coefficients a
1.3. [hz,hp,ht] = zplane(___)
1.3.1. Return the handle vectors to zero lines, hz, and hp pole lines. Ht is a handle vector for the circle line of axes/unit and text objects.
1.4. zplane(d)
1.4.1. Finds the transfer function's zeros and poles represented by the digital filter, d
1.5. [vz,vp,vk] = zplane(d)
1.5.1. Returns the zeros (vector vz), poles (vector vp), and gain (scalar vk) corresponding to the digital filter d
2. Usage in ECG
2.1. Uses a property of poles and zeros position on Z domain
2.2. Relationship between the pole pattern in the z-plane and component wave pattern in the time signal is established
2.3. Use of the result that IDCT of the impulse response of a second-order system function with 2 poles and 2 zeros gives a bell-shaped biphasic wave called a fractional component and vice versa
3. Input Argument
3.1. z, p — Zeros and poles
3.1.1. Zeros and poles, specified as column vectors or matrices
3.2. b, a — Transfer function coefficients row vectors
3.2.1. Transfer function coefficients, specified as row vectors. The transfer function is defined in terms of z–1: H(z) = B(z) / A(z) = b(1)+b(2)z−1+⋯+b(n+1)z−n / a(1)+a(2)z−1+⋯+a(m+1)z−m
3.3. d — Digital filter
3.3.1. Digital filter, specified as a digitalFilter object
4. Output Argument
4.1. hz, hp, ht — Vectors of handles vectors
4.1.1. Vectors of handles to the zero lines, hz, and the pole lines, hp, of the pole-zero plot
4.2. vz, vp, vk — Zeros, poles, and gain column vectors and scalar
4.2.1. Zeros, poles, and gain of a digital filter, d, returned as column vectors and a scalar