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The Inverse of Winnowing: a Fortran Subroutine and Discussion of Unwinnowing Discrete Data

By Robert E. Bracken


Open-File Report 03-229


Version 1.0
Published 2004
This report describes an unwinnowing algorithm that utilizes a discrete Fourier transform, and a resulting Fortran subroutine that winnows or unwinnows a 1-dimensional stream of discrete data; the source code is included. The unwinnowing algorithm effectively increases (by integral factors) the number of available data points while maintaining the original frequency spectrum of a data stream. This has utility when an increased data density is required together with an availability of higher order derivatives that honor the original data.

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OFR-03-229 PDF file (340 KB) (This version of the report is accessible as defined in Section 508.)
Download Program ASCII file
Source code for all of the subroutines logo