Questions tagged [scipy]
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17
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6
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3
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Role of window length and overlap in uncertainty principle?
I am trying to predict epilepsy using spectrograms and a convolutional neural network.
So far I have achieved a validation accuracy of 86% which i feel like is pretty good. Lots of the papers doing ...
2
votes
2
answers
690
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Amplitude extraction using STFT
I'm trying to recover amplitude/magnitude from an audio stream. I'm using FFT to go from time domain to frequency.
If I feed in a signal of known amplitude, the results I get from either windowing or ...
- 243
11
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5
answers
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Why is Scipy implementation of Hilbert() function different from Matlab implementation of the function?
I am trying to fit Hilbert envelop to a high frequency ultrasonic signal of frequency 250 KHZ and sampling rate 12000000. Raw signal looks like below: .
I used hilbert() function from scipy.signal ...
- 213
8
votes
1
answer
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Scipy resample, "fourier method" explanation
I am seeking explanation of what "Fourier method" is that is described for resampling in documentation of resample() method. I want to downsample an array. I know what decimation is and how it works, ...
- 83
4
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1
answer
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How to generate random samples of Gaussian distribution directly in the frequency domain?
One can easily draw (pseudo-)random samples from a normal (Gaussian) distribution by using, say, NumPy:
...
4
votes
2
answers
517
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Why doesn't the convolution of the impulse response match the system's output?
If you define an LTI system sys in scipy, you may conveniently feed an input x to it to get ...
- 83
3
votes
1
answer
591
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Compute minimum phase version of a FIR
I am working with HRIR filters, in particular I am trying to interpolate them.
One commod method in the literature to perform interpolation of HRIR is to use the minimum-phase decomposition and ...
3
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1
answer
4k
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How to implement bandpass filter on complex valued signal?
I am using Scipy to implement bandpass filter but it assumes that positive normalized frequency is passed but I & Q samples range from [Fc-Fs/2,Fc+Fs/2] where Fs is sampling frequency & Fc is ...
- 47
2
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2
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Why does python's scipy.signal.dimpulse introduce delay in impulse response?
Consider a simple linear, time invariant system of the form:
$y_k = cy_{k-1} + (1-c)x_k$
The impulse response of this system can be computed by either dimpulse or by applying lfilter to a vector ...
- 375
2
votes
1
answer
1k
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filtering EEG data with scipy.signal
I have EEG data recorded with a sampling rate of 256 Hz. Each recording contains 19 EEG channels. Other channels (like ECG data) are ignored. The recordings of 10 patients are 20 minutes long each, ...
- 153
1
vote
1
answer
430
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IIR design: SciPy CMSIS-DSP coefficient format
How do you reconcile Scipy.signal's IIR design with CMSIS-DISP's API? Scipy.signal outputs in one of 3 forms:
Numerator/denominator
Pole Zero
Second-Order-Sections.
CMSIS requires an array of length ...
- 113
1
vote
1
answer
135
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using scipy.signal.sosfilt to filter a stereo signal with zi, zf
I'm stuck trying to filter a two-channel signal using sosfilt() with the zi initial state. I need to use the zi parameter so I can carry the filter state over ...
- 185
1
vote
2
answers
607
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Scipy and Matlab Spectrogram not matching
I am trying to replicate a spectrogram from MATLAB in Python. I've read other posts but they either don't use complex data or the data doesn't match between languages.
I've defined my FFT length (<...
- 151
1
vote
1
answer
1k
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CWT at low scales: PyWavelets vs Scipy
Low scales are arguably the most challenging to implement due to limitations in discretized representations. Detailed comparison here; the principal difference is in how the two handle wavelets at ...
- 8,805
0
votes
0
answers
298
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Jerk detection in accelerometer data
I want to detect jerk from accelerator data i.e. values beyond 1.57 m/s^2, but due to the high frequency nature of the sensor (400 values per second), it gives multiple jerks instead of one.
How can I ...
- 11
0
votes
1
answer
2k
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Demodulation of FSK signal
What kind of FSK signal is this and what demodulation technique can I use to demodulate it. Why is the phase of the 1's changing like that and how does that effect how it needs to be demodulated. I ...
- 275
0
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1
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121
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Filter design for an unusual EEG experiment
I'm designing a quite unusual (in terms of signal analysis) EEG experiment, which forces me to design my own filter. I have never done this before, so kindly please check my work and suggest ...
