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    Designs filter coefficients for a smoothing filter. You can use this node to design a moving-average FIR filter or an exponentially-averaging IIR filter.

    Programming Patterns

    To implement either an FIR or IIR filter, pass the outputs of this node to IIR Filter.

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    type

    The type of smoothing filter to design.

    moving average

    Yields forward-only (FIR) coefficients.

    exponential

    Yields first-order IIR coefficients.

    Default: moving average

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    half-width

    Half-width of the moving-average filter in samples. For a half-width of M, the full width of the moving-average filter is N = 1 + 2M samples. Therefore, the full width N is always an odd number of samples.

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    shape

    The shape of the moving-average filter.

    rectangular

    Applies a rectangular moving-average filter to the samples. All samples in the moving-average window are weighted equally in computing each smoothed output sample.

    triangular

    Applies a triangular moving-average filter to the samples. The peak is centered in the middle of the moving-average window, ramping down symmetrically on both sides of the center sample.

    Default: rectangular

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    time constant

    Time constant of the exponential-weighting filter in seconds.

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    fs

    Sampling frequency in samples per second.

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    reverse coefficients

    The reverse, or feedback, coefficients of an IIR filter.

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    forward coefficients

    The forward coefficients of an IIR filter.

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    error

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