R/hamming.R

In signal: Signal Processing

## Copyright (C) 1995, 1996, 1997  Andreas Weingessel
##
## This file is part of Octave.
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## any later version.
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## -*- texinfo -*-
## @deftypefn {Function File} {} hamming (@var{m})
## Return the filter coefficients of a Hamming window of length @var{m}.
##
## For a definition of the Hamming window, see e.g. A. V. Oppenheim &
## R. W. Schafer, "Discrete-Time Signal Processing".
## @} # deftypefn

## Author: AW <Andreas.Weingessel@ci.tuwien.ac.at>
## Description: Coefficients of the Hamming window

hamming  <- function(n)  { 

  if (! (n == round (n) && n > 0))
    stop("hamming: n has to be an integer > 0")

  if (n == 1)
    c = 1
  else {
    n = n - 1
    c = 0.54 - 0.46 * cos (2 * pi * (0:n) / n)
  } 
  c
}