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iopzmap

Plot pole-zero map for input-output pairs of dynamic system using default options

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    Syntax

    iopzmap(sys)
    iopzmap(sys1,sys2,...,sysN)
    iopzmap(sys1,ColorSpec1,...,sysN,ColorSpecN)

    Description

    iopzmap(sys) plots the poles and zeros of each input/output pair of the dynamic system model sys. In the plot, x and o represent poles and zeros, respectively.

    For model arrays, iopzmap plots the poles and zeros of each model in the array on the same diagram.

    example

    iopzmap(sys1,sys2,...,sysN) plots poles and zeros for multiple models in a single plot. The models can have different numbers of inputs and outputs and can be a mix of continuous and discrete systems.

    iopzmap(sys1,ColorSpec1,...,sysN,ColorSpecN) sets the color for the plot of each system. For more plot customization options, use iopzplot.

    Examples

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    Open Live Script

    Create a one-input, two-output dynamic system.

    H = [tf(-5 ,[1 -1]); tf([1 -5 6],[1 1 0])];

    Plot a pole-zero map.

    iopzmap(H)

    MATLAB figure

    iopzmap generates a separate map for each I/O pair in the system.

    This example uses:

    Open Live Script

    View the poles and zeros of an over-parameterized state-space model estimated from input-output data. (Requires System Identification Toolbox™).

    load iddata1
sys = ssest(z1,6,ssestOptions('focus','simulation'));
iopzmap(sys)

    MATLAB figure

    The plot shows that there are two pole-zero pairs that almost overlap, which hints are their potential redundancy.

    Input Arguments

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    Dynamic system, specified as a SISO or MIMO dynamic system model or array of dynamic system models. Dynamic systems that you can use include:

    • Continuous-time or discrete-time numeric LTI models, such as tf, zpk, or ss models.

    • Sparse state-space models, such as sparss or mechss models.

    • Generalized or uncertain LTI models such as genss or uss (Robust Control Toolbox) models. Using uncertain models requires Robust Control Toolbox™ software.

      • For tunable control design blocks, the function evaluates the model at its current value to plot the response.

      • For uncertain control design blocks, the function plots the nominal value and random samples of the model.

    • Identified LTI models, such as idtf (System Identification Toolbox), idss (System Identification Toolbox), or idproc (System Identification Toolbox) models. Using identified models requires System Identification Toolbox™ software.

    If sys is an array of models, the plot shows responses of all models in the array on the same axes.

    Color, specified as one of the following values.

    ColorDescription
    "r"red
    "g"green
    "b"blue
    "c"cyan
    "m"magenta
    "y"yellow
    "k"black
    "w"white

    Tips

    • Use sgrid or zgrid to plot lines of constant damping ratio and natural frequency in the s-plane or z-plane, respectively.

    • For additional options for customizing the appearance of the pole-zero plot, use iopzplot.

    Version History

    Introduced before R2006a

    See Also

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