Steven G. Johnson

Last updated
Steven G. Johnson
Born1973
NationalityAmerican
Alma mater MIT
Known for FFTW
Awards DoD NDSEG Fellowship (1996)
J. H. Wilkinson Prize for Numerical Software (1999)
Scientific career
Fields
Institutions MIT
Thesis Photonic Crystals: From Theory to Practice  (2001)
Doctoral advisor John Joannopoulos
Website math.mit.edu/~stevenj/

Steven Glenn Johnson (born 1973) [2] is an American mathematician known for being a co-creator of the FFTW [3] [4] [5] library for software-based fast Fourier transforms and for his work on photonic crystals. He is professor of Applied Mathematics and Physics at MIT where he leads a group on Nanostructures and Computation. [6]

While working on his PhD at MIT, he developed the Fastest Fourier Transform in the West (FFTW) library [3] with funding from the DoD NDSEG Fellowship. [7] Steven Johnson and his colleague Matteo Frigo were awarded the 1999 J. H. Wilkinson Prize for Numerical Software for this work. [8] [9]

He is the author of the NLOpt library for nonlinear optimization. He is a frequent contributor to the Julia programming language, and has also contributed to Python, R, and Matlab. He was a keynote speaker for the 2019 JuliaCon conference. [10]

Related Research Articles

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<span class="mw-page-title-main">Discrete Fourier transform</span> Type of Fourier transform in discrete mathematics

In mathematics, the discrete Fourier transform (DFT) converts a finite sequence of equally-spaced samples of a function into a same-length sequence of equally-spaced samples of the discrete-time Fourier transform (DTFT), which is a complex-valued function of frequency. The interval at which the DTFT is sampled is the reciprocal of the duration of the input sequence. An inverse DFT (IDFT) is a Fourier series, using the DTFT samples as coefficients of complex sinusoids at the corresponding DTFT frequencies. It has the same sample-values as the original input sequence. The DFT is therefore said to be a frequency domain representation of the original input sequence. If the original sequence spans all the non-zero values of a function, its DTFT is continuous, and the DFT provides discrete samples of one cycle. If the original sequence is one cycle of a periodic function, the DFT provides all the non-zero values of one DTFT cycle.

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<span class="mw-page-title-main">David H. Bailey (mathematician)</span> American mathematician (born 1948)

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James William Cooley was an American mathematician. Cooley received a B.A. degree in 1949 from Manhattan College, Bronx, NY, an M.A. degree in 1951 from Columbia University, New York, NY, and a Ph.D. degree in 1961 in applied mathematics from Columbia University. He was a programmer on John von Neumann's computer at the Institute for Advanced Study, Princeton, NJ, from 1953 to 1956, where he notably programmed the Blackman–Tukey transformation.

<span class="mw-page-title-main">FFTW</span> Software library for computing discrete Fourier transforms

The Fastest Fourier Transform in the West (FFTW) is a software library for computing discrete Fourier transforms (DFTs) developed by Matteo Frigo and Steven G. Johnson at the Massachusetts Institute of Technology.

The James H. Wilkinson Prize for Numerical Software is awarded every four years to honor outstanding contributions in the field of numerical software. The award is named to commemorate the outstanding contributions of James H. Wilkinson in the same field.

Intel oneAPI Math Kernel Library is a library of optimized math routines for science, engineering, and financial applications. Core math functions include BLAS, LAPACK, ScaLAPACK, sparse solvers, fast Fourier transforms, and vector math.

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<span class="mw-page-title-main">Alan Edelman</span> American mathematician

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The vector-radix FFT algorithm, is a multidimensional fast Fourier transform (FFT) algorithm, which is a generalization of the ordinary Cooley–Tukey FFT algorithm that divides the transform dimensions by arbitrary radices. It breaks a multidimensional (MD) discrete Fourier transform (DFT) down into successively smaller MD DFTs until, ultimately, only trivial MD DFTs need to be evaluated.

<span class="mw-page-title-main">Bailey's FFT algorithm</span> High-performance algorithm

The Bailey's FFT is a high-performance algorithm for computing the fast Fourier transform (FFT). This variation of the Cooley–Tukey FFT algorithm was originally designed for systems with hierarchical memory common in modern computers. The algorithm treats the samples as a two dimensional matrix and executes short FFT operations on the columns and rows of the matrix, with a correction multiplication by "twiddle factors" in between.

References

  1. "Steven Johnson | MIT Mathematics". math.mit.edu. Retrieved 27 February 2020.
  2. "Johnson, Steven G., 1973-". viaf.org. Retrieved 27 February 2020.
  3. 1 2 Frigo M, Johnson SG (February 2005). "The design and implementation of FFTW3" (PDF). Proceedings of the IEEE. 93 (2): 216–231. CiteSeerX   10.1.1.66.3097 . doi:10.1109/JPROC.2004.840301. S2CID   6644892.
  4. Frigo M, Johnson SG (1998). "FFTW: An adaptive software architecture for the FFT". Proceedings of the 1998 IEEE International Conference on Acoustics, Speech and Signal Processing, ICASSP '98 (Cat. No.98CH36181). Vol. 3. pp. 1381–1384. CiteSeerX   10.1.1.47.8661 . doi:10.1109/ICASSP.1998.681704. ISBN   978-0-7803-4428-0. S2CID   12560207.
  5. Johnson SG, Frigo M (September 2008). "ch.11: Implementing FFTs in practice". In C. S. Burrus (ed.). Fast Fourier Transforms. Houston TX: Connexions: Rice University.
  6. "Steven Johnson | MIT Mathematics". math.mit.edu. Retrieved 27 February 2020.
  7. Frigo M, Johnson SG (September 11, 1997). "The Fastest Fourier Transform in the West" (PDF). MIT Labroratory for Computer Science.
  8. "THE WILKINSON PRIZE FOR NUMERICAL SOFTWARE". Numerical Algorithms Group. Retrieved 22 November 2017.
  9. SIAM. "James H. Wilkinson Prize for Numerical Software". Society for Industrial and Applied Mathematics. Retrieved 22 November 2017.
  10. Herriman, Jane (29 March 2019). "Steven Johnson as a JuliaCon 2019 keynote speaker!". Julia Discourse. Retrieved 29 March 2019.