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The inverse of winnowing: a FORTRAN subroutine and discussion of unwinnowing discrete data

January 1, 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.

Publication Year 2004
Title The inverse of winnowing: a FORTRAN subroutine and discussion of unwinnowing discrete data
DOI 10.3133/ofr03229
Authors Robert E. Bracken
Publication Type Report
Publication Subtype USGS Numbered Series
Series Title Open-File Report
Series Number 2003-229
Index ID ofr03229
Record Source USGS Publications Warehouse