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Docs: add example #96
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@@ -8,6 +8,7 @@ makedocs( | |
pages = Any[ | ||
"Home" => "index.md", | ||
"API" => "fft.md", | ||
"Examples" => "examples.md", | ||
], | ||
) | ||
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# Examples | ||
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Here you can find some basic examples of how to use this package. | ||
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## Spectrum of a 1D Signal | ||
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This example shows how to obtain and plot the spectrum of a simple, real-valued signal with a second-order harmonic using FFTW and [Plots](https://github.com/JuliaPlots/Plots.jl). | ||
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```julia | ||
using Plots | ||
using FFTW | ||
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# Number of points | ||
N = 2^12 - 1 | ||
# Sample spacing | ||
Ts = 1 / (1.1 * N) | ||
# Sample rate | ||
fs = 1 / Ts | ||
# Start time | ||
t0 = 0 | ||
tmax = t0 + N * Ts | ||
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# time coordinate | ||
t = t0:Ts:tmax | ||
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signal = sin.(2π * 60 * t) + .5 * sin.(2π * 120 * t) | ||
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# Fourier Transform of it | ||
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F = fftshift(fft(signal)) | ||
freqs = fftshift(fftfreq(length(t), fs)) | ||
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# Plot | ||
time_domain = plot(t, signal, title="Signal", xlims=(0, 4 / 60), xlabel="time (s)", label="") | ||
freq_domain = plot(freqs, abs.(F), title="Spectrum", xlims=(0, 200), xlabel="frequency (Hz)", label="") | ||
plot(time_domain, freq_domain, layout = 2) | ||
savefig("Wave.pdf") | ||
There was a problem hiding this comment. Choose a reason for hiding this commentThe reason will be displayed to describe this comment to others. Learn more. We could consider make this a Documenter There was a problem hiding this comment. Choose a reason for hiding this commentThe reason will be displayed to describe this comment to others. Learn more. (Btw, you don't have to make this change as part of this PR unless you want to. I mention it more as a note.) |
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``` | ||
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![](img/1D60Hz.png) |
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together, this is equivalent to saying that the sample rate is
1.1 * N
Hz, i.e. 4504.5