Wolfram Function Repository
Instant-use add-on functions for the Wolfram Language
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Create a fast Fourier transform calculation in graphical form
ResourceFunction["FastFourierGraph"][dim] returns an edge-weighted, time-ordered multiway graph on 2dim×2dim vertices, which describes the fast Fourier transform of a length 2dim vector. | |
ResourceFunction["FastFourierGraph"][data] takes a list of data with length 2dim and adds it to the graph under the annotation key VertexWeight. |
Calculate the graph for the base case of the fast Fourier transform:
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Plot the next induced case:
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Color edges according to phases:
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Notice n log n complexity in rectangular dimensions of subsequent graphs:
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Blow up the graphs to see their free-form structure using "SpringElectricalEmbedding":
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Create a graph from data:
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Use the option "ComputeValues"→True to compute the transformation values while generating the graph:
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See the fast Fourier transformation values by retrieving the VertexWeight:
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Depict results of the calculation as above:
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Compare with the standard method using FourierMatrix:
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Apply a similar validation technique for different input lengths:
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Input should be a list of length 2n for some integer n>0:
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Timing statistics look very slow compared to the built-in Fourier:
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Compile time is relatively slow compared to ButterflyGraph:
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Follow the different paths a value can take from input to output:
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Plot an intensity profile:
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