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getQualityFactor

Get quality factor

Description

example

Q = getQualityFactor(npFilter) returns the quality factor (Q factor) of the notch peak filter. The Q factor is defined as the center frequency divided by the bandwidth.

Examples

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Create a dsp.NotchPeakFilter object in the default configuration, where the Specification property is set to 'Bandwidth and center frequency'.

np = dsp.NotchPeakFilter
np = 
  dsp.NotchPeakFilter with properties:

      Specification: 'Bandwidth and center frequency'
          Bandwidth: 2205
    CenterFrequency: 11025
         SampleRate: 44100

Determine the quality factor of the filter using the getQualityFactor function. The quality factor is given by the ratio of the center frequency to the bandwidth.

getQualityFactor(np)
ans = 5

Visualize the filter response using fvtool.

fvtool(np)

Figure Filter Visualization Tool - Magnitude Response (dB) contains an axes and other objects of type uitoolbar, uimenu. The axes with title Magnitude Response (dB) contains an object of type line.

Input Arguments

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Notch peak filter whose quality factor is computed, specified as a dsp.NotchPeakFilter object.

Output Arguments

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Quality factor of the filter, returned as a scalar. The Q factor is defined as the center frequency divided by the bandwidth.

Data Types: double

Introduced in R2014a