Functions > Transforms and Filters > Example: dft and idft of a Vector
  
Example: dft and idft of a Vector
Use the dft and idft functions for finding the forward or inverse Discrete Fourier Transform of a vector.
1. Define the length of a data vector.
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2. Use the exp function to create a real data vector of length N.
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3. Plot the data.
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4. Use the dft function to calculate the Discrete Fourier Transform of V.
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5. Plot the absolute values of Z.
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6. Show the definition of the dft function.
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7. Use the above definition to find a specific frequency element and compare it with the corresponding element in the output of the dft function.
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Gaussian idft
The idft function is the inverse transform of dft. It accepts a real or complex vector as its argument and returns a vector of the same length.
1. Show that the inverse transform of a dft function is the function itself.
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2. Use the previously defined vector V, then show that the inverse of the dft of V is V itself.
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3. Show the definition of idft function.
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4. Use the above definition to find a specific frequency element and compare it with the corresponding element in the output of the idft function and vector V.
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