BLISRetreat Tze Meng Low, CMU <p xmlns:svg="http://www.w3.org/2000/svg" id="p-116">Small Prime DFTs as Specialized Matrix Vector Multiplies</p>

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Unit 4.4.4 Tze Meng Low, CMU
Small Prime DFTs as Specialized Matrix Vector Multiplies

Abstract. Small prime-sized discrete Fourier transforms (DFTs) are often implemented using O(nlogn) algorithms. These algorithms often incur complex indexing and expensive data movement. In this work, we present an alternative method by casting the Fourier transform as a specialized symmetric matrix-vector multiplication. We show that this approach can be twice as fast as existing libraries on various Intel and AMD CPUs.

"In conclusion" slide (click on picture to enlarge) . For higher resolution, view the PDF.

Unit 4.4.4 Tze Meng Low, CMU Small Prime DFTs as Specialized Matrix Vector Multiplies

Unit 4.4.4 Tze Meng Low, CMU
Small Prime DFTs as Specialized Matrix Vector Multiplies