I have four cosines with frequencies 400e-3, 500e-3, 600e-3 and 700e-3 and I am trying to do the FFT of them but under the time I need, I cannot distinguish the four. Is there a way to distinguish the peaks without changing the tmax time of 1.76 and the frequencies? Here are the results: Answer The solution was to increase
Tag: fft
Scipy ifft gives different results with seemingly identical input
Why would xcorr and xcorr2 be quite different here? M1 and M2 are numpy matrices. M1.shape[0] = M2.shape[0]. xcorr is what I would expect with this operation, but xcorr2 is something totally different and has imaginary numbers. xcorr does not have imaginary numbers. Answer Try giving xcorr and xcorr2 dtype=complex. According to scipy docs, the output from both fft and
How do I plot an fft in python using scipy and modify the frequency range so that it shows the two peaks frequencies in the center?
The following Python code uses numpy to produce a frequency plot of a sinusoid graph : Based on the code above , we are plotting a sine wave with two frequencies, one at 50Hz and another at 80 Hz. You can clearly see the Fourier transform plot shows peaks at those two frequencies. My question: How do I modify the
What does np.fft.fftfreq actually do?
I have a monthly time series and I am taking the discrete fourier transform of it. However I am confused as to how numpy converts the time domain into frequency domain? I am using np.fft.fftfreq and my time array is is 708 indices long and each measurement of the data is computed every month. This is the output frequency using
How to set all values between a range equal to zero in python [closed]
Closed. This question needs to be more focused. It is not currently accepting answers. Want to improve this question? Update the question so it focuses on one problem only by editing this post. Closed 2 years ago. Improve this question I want to set all the values between 0.75 and 0.8 of an array, equal to zero. Until now I
Python spectrogram in 3D (like matlab’s spectrogram function)
My question is the following: I have all the values that I need for a spectrogram (scipy.fftpack.fft). I would like to create a 3D spectrogram in python. In MATLAB this is a very simple task, while in python it seems much more complicated. I tried mayavi, 3D plotting matplotlib but I have not managed to do this. Thanks My code: