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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  Take Pride in America button