setSampleRate

Set sample rate of digital filter

Since R2026a

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    Syntax

    setSampleRate(d,Fs)

    Description

    setSampleRate(d,Fs) sets the sample rate Fs to the digital filter d.

    example

    Examples

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    Open Live Script

    Design two digital filters with these specifications:

    • A lowpass IIR filter with passband and stopband frequencies of 0.65π rad/sample and 0.80π rad/sample, respectively. The passband ripple is 1 dB and the stopband attenuation is 50 dB.

    • A bandstop IIR filter with passband ripples of 1 dB and stopband attenuation of 50 dB. The passband frequencies are 0.25π rad/sample and 0.34π rad/sample. The stopband frequencies are 0.36π rad/sample and 0.45π rad/sample.

    d1 = designfilt("lowpassiir", ...
    PassbandFrequency=0.65,StopbandFrequency=0.80, ...
    PassbandRipple=1,StopbandAttenuation=50);
d2 = designfilt("bandstopiir", ...
    PassbandFrequency1=0.25,StopbandFrequency1=0.34, ...
    StopbandFrequency2=0.36,PassbandFrequency2=0.45, ...
    PassbandRipple1=1,StopbandAttenuation=50, ...
    PassbandRipple2=1);

    Cascade the lowpass IIR and bandstop IIR filters to form a digital filter cascade. The filter uses normalized frequency.

    d = cascade(d1,d2)
    d = 
 digitalFilter cascade with properties:

   Stages:
                 Stage1: [1×1 digitalFilter]
                 Stage2: [1×1 digitalFilter]

   Specifications:
    NormalizedFrequency: 1

 Use filterAnalyzer to visualize filter
 Use filter to filter data

    Set the sample rate of the digital filter cascade to 2.5 kHz and display the filter properties. The filter uses the specified sample rate.

    setSampleRate(d,2.5e3)
d
    d = 
 digitalFilter cascade with properties:

   Stages:
                 Stage1: [1×1 digitalFilter]
                 Stage2: [1×1 digitalFilter]

   Specifications:
    NormalizedFrequency: 0
             SampleRate: 2500

 Use filterAnalyzer to visualize filter
 Use filter to filter data

    Display the SampleRate property for each stage of the digital filter cascade. Each stage uses the specified sample rate.

    d.Stage1.SampleRate
    ans = 
2500

    d.Stage2.SampleRate
    ans = 
2500

    Input Arguments

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    Digital filter, specified as a digitalFilter object. Use designfilt to generate a digital filter based on frequency-response specifications.

    Example: d = designfilt("lowpassiir",FilterOrder=3,HalfPowerFrequency=0.5) specifies a third-order Butterworth filter with normalized 3 dB frequency 0.5π rad/sample.

    Sample rate of the cascaded filter, specified as one of these:

    • "normalized" — setSampleRate sets the digital filter d to use normalized frequency.

    • Positive scalar — setSampleRate sets the sample rate of the digital filter d to Fs Hz.

    Data Types: char | string | single | double

    Version History

    Introduced in R2026a

    See Also

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