Plotting window functions
8 kwietnia 2010 00:33
This is a very simple way to get a preview of window function shape. The example uses Aquila::TextPlot as a drawing tool. Windows are drawn as simple asterisk patterns.
#include "aquila/source/window/BarlettWindow.h" #include "aquila/source/window/BlackmanWindow.h" #include "aquila/source/window/FlattopWindow.h" #include "aquila/source/window/HammingWindow.h" #include "aquila/source/window/HannWindow.h" #include "aquila/source/window/RectangularWindow.h" #include "aquila/tools/TextPlot.h" int main(int argc, char *argv[]) { const std::size_t LENGTH = 65; Aquila::TextPlot plot; Aquila::BarlettWindow barlett(LENGTH); plot.setTitle("Barlett"); plot.plot(barlett); Aquila::BlackmanWindow blackman(LENGTH); plot.setTitle("Blackman"); plot.plot(blackman); Aquila::FlattopWindow flattop(LENGTH); plot.setTitle("Flattop"); plot.plot(flattop); Aquila::HammingWindow hamming(LENGTH); plot.setTitle("Hamming"); plot.plot(hamming); Aquila::HannWindow hann(LENGTH); plot.setTitle("Hann"); plot.plot(hann); Aquila::RectangularWindow rect(LENGTH); plot.setTitle("Rectangular"); plot.plot(rect); return 0; }
The windows are plotted below for comparison. Note: the rectangular window is improperly scaled at the moment and looks like it's all zeros. It isn't, that is a constant 1.
Barlett
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Blackman
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Flat-top
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Hamming
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Hann
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Rectangular
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