Error in extract_features

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1

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Dear All,

I am trying to extract features from EEG using feature extraction api (
https://mne-tools.github.io/mne-features/api.html)

I am getting following error:

TypeError: set_params() argument after ** must be a mapping, not numpy.ndarray

The code used is below:

selected_funcs = {'std', 'kurtosis','pow_freq_bands'}
pow_freq_bands__freq_bands = array([0.5, 4., 8., 13., 30.])
X_new = extract_features(epochs_data, raw.info['sfreq'], selected_funcs,
pow_freq_bands__freq_bands)

Thank you
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2

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hi,

do the examples we provide work? does it break only with your data?

Alex

3

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Hi Alex,

This given example working fine for my dataset as well.

selected_funcs = {'std', 'kurtosis'}
pow_freq_bands__freq_bands = array([0.5, 4., 8., 13., 30.])
X_new = extract_features(epochs_data, raw.info['sfreq'], selected_funcs)

The problem comes when I try to select a function which has parameters and
which shoud pass to the extract_features() sepeately. In this case,
pow_freq_bands__freq_bands. Also I couldn't find such examples in internet.

Code which gives the error:
selected_funcs = {'std', 'kurtosis','pow_freq_bands'}
pow_freq_bands__freq_bands = array([0.5, 4., 8., 13., 30.])
X_new = extract_features(epochs_data, raw.info['sfreq'], selected_funcs,
pow_freq_bands__freq_bands)

Thank you.

4

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hi,

the syntax should be:

X_new = extract_features(epochs_data, raw.info['sfreq'],
selected_funcs, {'pow_freq_bands__freq_bands': array([0.5, 4., 8.,
13., 30.])})

it's usually a good practice to look at tests to understand the usage.

https://github.com/mne-tools/mne-features/blob/master/mne_features/tests/test_feature_extraction.py#L43

HTH
Alex

5

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Dear Alex,

Thank you, That works.

I am from Colombo, Sri Lanka and today only I could check it.

Best regards,

Senaka