setExtractorParameters

Set nondefault values for feature extractor object

Since R2021b

Syntax

setExtractorParameters(sFE,featurename,params)

setExtractorParameters(sFE,featurename)

Description

setExtractorParameters(sFE,featurename,params) specifies the parameters used to extract featurename.

setExtractorParameters(sFE,featurename) sets the parameters used to extract featurename to their default values.

Examples

Set Parameter Values for Feature Extraction

Create a signalFrequencyFeatureExtractor object to extract the Welch power spectral density (PSD) estimate of a signal consisting of a 100 Hz sinusoid in additive N(0,1) white noise. The sample rate is 1 kHz and the signal has a duration of 5 seconds.

fs = 1000;
t = 0:1/fs:5-1/fs;
x = cos(2*pi*100*t) + randn(size(t));

sFE = signalFrequencyFeatureExtractor(SampleRate=fs,WelchPSD=true);

For the PSD computation, set the OverlapLength to 25 samples and the FFTLength to 512 samples. Call the getExtractorParameters function on the object to view the PSD parameters.

setExtractorParameters(sFE,"WelchPSD",OverlapLength=25,FFTLength=1024)
params = getExtractorParameters(sFE,"WelchPSD")

params = struct with fields:
          FFTLength: 1024
    FrequencyVector: []
      OverlapLength: 25
             Window: []

Use the extract function to extract the Welch's PSD estimate of the signal. Plot the result.

feature = extract(sFE,x);

fvec = linspace(0,fs/2,length(feature));
plot(fvec,pow2db(abs(feature)))

xlabel("Frequency (Hz)")
ylabel("PSD (dB/Hz)")
grid

Input Arguments

sFE — Feature extractor object

signalFrequencyFeatureExtractor object

Feature extractor object, specified as a signalFrequencyFeatureExtractor object.

featurename — Extracted feature

string scalar | character vector

Extracted feature, specified as a string scalar or a character vector.

Data Types: char | string

params — Parameters

name-value arguments | structure

Parameters used to extract featurename, specified as name-value arguments or a structure.

Data Types: string | struct

Extended Capabilities

GPU Arrays

Accelerate code by running on a graphics processing unit (GPU) using Parallel Computing Toolbox™.

This function fully supports GPU arrays. For more information, see Run MATLAB Functions on a GPU (Parallel Computing Toolbox).

Version History

Introduced in R2021b

R2023a: Use gpuArray inputs

The setExtractorParameters function supports gpuArray inputs. You must have Parallel Computing Toolbox™ to use this functionality.