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    Generates the set of filter coefficients to implement an IIR filter as specified by the Chebyshev filter model.

    Programming Patterns

    You can pass these coefficients to IIR Cascade Filter to filter a sequence of data.

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    filter structure option

    The order of the IIR cascade filter in IIR filter cluster.

    IIR 2nd Order 0 Returns IIR second-order filter stages.
    IIR 4th Order 1 Returns IIR fourth-order filter stages.
    Auto Select 2 Returns either IIR second-order or IIR fourth-order filter stages according to the filter type. If filter type is Lowpass or Highpass, this node returns IIR second-order filter stages. If filter type is Bandpass or Bandstop, this node returns IIR fourth-order filter stages.

    Default: 2—Auto Select

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    filter type

    The passband of the filter.

    Lowpass

    Uses a lowpass filter, which causes this node to return IIR second-order filter stages.

    Highpass

    Uses a highpass filter, which causes this node to return IIR second-order filter stages.

    Bandpass

    Uses a bandpass filter, which causes this node to return IIR fourth-order filter stages.

    Bandstop

    Uses a bandstop filter, which causes this node to return IIR fourth-order filter stages.

    Default: Lowpass

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    sampling frequency

    The sampling frequency in Hz.

    If this value is less than or equal to zero, the node returns an error as well as an empty array for IIR filter cluster.

    Default: 1.0 Hz

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    high cutoff frequency

    The high cutoff frequency, in Hz.

    The node places the following restrictions on this parameter according to filter type:

    filter type Restrictions
    0 (Lowpass) or 1 (Highpass) The node ignores this input.
    2 (Bandpass) or 3 (Bandstop) This value must be greater than low cutoff frequency and less than half of sampling frequency. It must also observe the Nyquist criterion.

    Default: 0.45

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    low cutoff frequency

    The low cutoff frequency in Hz. This value must observe the Nyquist criterion. When filter type is 2 (Bandpass) or 3 (Bandstop), this value must be less than high cutoff freq: fh.

    Default: 0.125 Hz

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    ripple

    The ripple in the passband, in decibels.

    This value must be greater than zero.

    Default: 0.1

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    order

    The order of the IIR filter.

    This value must be greater than zero.

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    IIR filter cluster

    The cascaded form of IIR filter coefficients.

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    filter structure

    Either IIR second-order or IIR fourth-order filter stages.

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    reverse coefficients

    The reverse coefficients of the IIR cascade filter.

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    Forward Coefficients

    The forward coefficients of the IIR cascade filter.

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    error

    A value that represents any error or warning that occurs when this node executes.