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11.3: Special Algorithms for input Data that is mostly Zero

  • Page ID
    2030
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    In some cases, most of the data to be transformed are zero. It is clearly wasteful to do arithmetic on that zero data. Another special case is when only a few DFT values are needed. It is likewise wasteful to calculate outputs that are not needed. We use a process called “pruning" to remove the unneeded operations.

    In other cases, the data are non-uniform sampling of a continuous time signal.

    There are certain applications where approximations to the DFT are all that is needed.

    Contributor

    • ContribEEBurrus

    This page titled 11.3: Special Algorithms for input Data that is mostly Zero is shared under a CC BY license and was authored, remixed, and/or curated by C. Sidney Burrus.

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