Linked Questions
63 questions linked to/from What do the X and Y axis stand for in the Fourier transform domain?
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How to Model a Parametric Fast Fourier Transform in Mathematica?
I'm using this code which evaluates the FFT of my original signal (which is a time series). Using the Manipulate function of Mathematica it is possible to vary the ...
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Getting frequency domain data from time domain using Fourier transformation [duplicate]
I have a dataset following cosine function [e.g. cos(200t)] in time domain. In frequency domain two sharp lines should appear at -200 and +200.
I have to do Fourier transform (or Fast Fourier ...
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Using Mathematica to take Fourier transform of data
i'm trying to use Mathematica to take a discrete Fourier transform of 68 data points (0 to 67) to perform further analysis.
My data points, when plotted, look like this:
Pretty straightforward.
Now, ...
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InverseFourier, Time response from the pressure over frequency
the problem I'm trying to solve is much more involved, that is I'm trying to get the Time Response for an Impulse Input for a loudspeaker starting from the pressure it generates over the frequency:.
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Obtaining better Fourier series for a piecewise constant function
I have the give wave-train:
and I extract the given set of points:
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An unknown defect with an approach in constructing scaled coordinates for obtaining and plotting Fourier series
I am having trouble scaling a set of coordinates and generating these coordinates into stepwise functions.
I start with the points from a plot:
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Is there a built-in equivalent to numpy's fftfreq?
I recently learned that python's numpy package contains a function called fftfreq (documented at numpy.fft.fftfreq) which is ...
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Fourier transform on analogue signal to frequency domain
Hi I have a question regarding the Fourier transform of an analogue signal measured in time domain.
The current 3 data is normalised, and it is expressed in percentage.
I have tried using this line of ...
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Fourier transform of a wave-profile [closed]
Hi I tried to do a Fourier transform of a series of points from a plot from ma wave-train profile.
The commands are as such
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Why does the reported primary frequency with Mathematica's discrete Fourier transform scale with the length of the input signal?
I am testing Mathematica's DFT algorithm using one of the test cases provided in the documentation, of a noisy sine function with a frequency of 0.15 cycles per sample:
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CommunityBot
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fast fourier transformation question
I was testing fft on mathematica using simple functions and ran into problems.
I first tried a simple cos function with the following code:
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How to fourier transform a numerical solution?
I numerically solved a wave equation and want to fourier transform the solution uwave1(t,x,z) at a particular instant of time t and position z. The code is as follows:
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Microfluctuations analysis and Power spectrum
I measured a parameter over time and obtained the values below:
0,627896 0,205004 0,259237 1,059125 0,832184 0,587992 0,565537 0,527323 0,460228 0,471958 0,26696 0,75367 ...
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How can I get the power spectrum density and separate low and high frequencies?
Good day everyone,
I'm new in mathematica.
I got these values over time (each value was obtained every 100 milliseconds):
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CommunityBot
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How to get the Inverse Fast Fourier Transform (ifft) of a dataset? [closed]
I'm looking at the inverse fast Fourier transform as calculated by Matlab. In the question "What's the correct way to shift zero frequency to the center of a Fourier Transform?" the way to ...
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