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About: DFT: Computational Complexity

Module by: Don Johnson. E-mail the author

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Name: DFT: Computational Complexity
ID: m0503
Language: English (en)
Summary: A brief explanation of calculation complexity and how the complexity of the discrete Fourier transform is order N squared.
Subject: Mathematics and Statistics, Science and Technology
Keywords: computational complexity, discrete fourier transform
Document Type: -//CNX//DTD CNXML 0.5 plus MathML//EN
License: Creative Commons Attribution License CC-BY 1.0

Authors: Don Johnson (
Copyright Holders: Don Johnson (
Maintainers: CJ Ganier (, Don Johnson (, John Cottrell (

Latest version: 2.11 (history)
First publication date: Jul 18, 2000 12:00 am -0500
Last revision to module: Apr 13, 2005 9:22 am -0500


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Version History

Version: 2.12 May 17, 2013 9:52 am -0500 by Don Johnson
Fixed a typo.

Version: 2.11 Apr 13, 2005 9:22 am -0500 by Charlet Reedstrom Currently viewing this version.
update to cnxml-0.5, update mathml

Version: 2.10 Jul 27, 2003 3:59 pm -0500 by Don Johnson
Fixed intermodule link errors.

Version: 2.9 Nov 20, 2002 12:00 am -0600 by (Unknown)
Fixed typos.

Version: 2.8 Aug 13, 2002 12:00 am -0500 by (Unknown)
Upgraded to 0.4.

Version: 2.7 Aug 3, 2002 12:00 am -0500 by (Unknown)
fixed some typos.

Version: 2.6 Apr 19, 2002 12:00 am -0500 by (Unknown)
audited for mathml and cnxml errors

Version: 2.5 Sep 11, 2001 12:00 am -0500 by Brent Hendricks
Converted to CNXML 0.3.5

Version: 2.4 Aug 22, 2001 12:00 am -0500 by (Unknown)
Made O() a function

Version: 2.3 Jul 17, 2001 12:00 am -0500 by (Unknown)
added keywords
made John Cottrell a maintainer
fixed minor errors

Version: 2.2 Jun 5, 2001 12:00 am -0500 by (Unknown)
Corrected big O notation to be a presentation ML notation rather than a function in Content ML.  Also fixed some capitalization.

Version: 2.1 May 31, 2001 12:00 am -0500 by (Unknown)
Replaced some emphasis with term.

Version: 2.0 Oct 17, 2000 12:00 am -0500 by Brent Hendricks
Bumped version to 2.0

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American Chemical Society (ACS) Style Guide:

Johnson, D. DFT: Computational Complexity, OpenStax_CNX Web site., Apr 13, 2005.

American Medical Assocation (AMA) Manual of Style:

Johnson D. DFT: Computational Complexity [OpenStax_CNX Web site]. April 13, 2005. Available at:

American Psychological Assocation (APA) Publication Manual:

Johnson, D. (2005, April 13). DFT: Computational Complexity. Retrieved from the OpenStax_CNX Web site:

Chicago Manual of Style (Bibliography):

Johnson, Don. "DFT: Computational Complexity." OpenStax_CNX. April 13, 2005.

Chicago Manual of Style (Note):

Don Johnson, "DFT: Computational Complexity," OpenStax_CNX, April 13, 2005,

Chicago Manual of Style (Reference, in Author-Date style):

Johnson, D. 2005. DFT: Computational Complexity. OpenStax_CNX, April 13, 2005.

Modern Languages Association (MLA) Style Manual:

Johnson, Don. DFT: Computational Complexity. OpenStax_CNX. 13 Apr. 2005 <>.