You are here: Frontpage : Introduction » Tutorials » The Discrete Fourier Transformation (DFT): Definition and numerical examples

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tutorial:the_discrete_fourier_transformation_dft [2013/01/30 14:03] Simon-Shlomo Poil |
tutorial:the_discrete_fourier_transformation_dft [2014/12/04 11:45] (current) Klaus Linkenkaer-Hansen [Background] |
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- Learn to work with complex numbers and complex functions. | - Learn to work with complex numbers and complex functions. | ||

+ | <note tip>You can run FFT analysis in the NBT toolbox ([[tutorial:download_and_install_nbt|]]) (using the Welch method). | ||

+ | |||

+ | See | ||

+ | |||

+ | [[tutorial:amplitude_in_classical_frequency_bands|]] | ||

+ | |||

+ | or | ||

+ | |||

+ | [[tutorial:power_spectra_wavelet_analysis_and_coherence|]]</note> | ||

===== Background ===== | ===== Background ===== | ||

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** Preparation for the tutorial ** | ** Preparation for the tutorial ** | ||

- | The commands on in this box ensure that the following exercise has all the necessary scripts and does not interfere with variables or graphics from previous exercises. If you come directly from another exercise it should be clear which commands you can skip. | + | The commands in this box ensure that the following exercise has all the necessary scripts and does not interfere with variables or graphics from previous exercises. If you come directly from another exercise it should be clear which commands you can skip. |

Start MATLAB and find your current working directory using 'pwd'. | Start MATLAB and find your current working directory using 'pwd'. | ||

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phs = 90/360; % the phase of the wave. | phs = 90/360; % the phase of the wave. | ||

- | [wave] = SignalGenerator_sin(frq, len, Fs, phs); % Generate a sine wave. | + | [wave] = signalgenerator_sin(frq, len, Fs, phs); % Generate a sine wave. |

</code> | </code> | ||

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<html> | <html> | ||

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