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Info-Mac 4
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Info_Mac IV CD-ROM (Pacific HiTech Inc.)(August 1994).iso
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Science
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RLaB
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window.r
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1994-04-25
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//---------------------------------------------------------------------------
// window.r
// Syntax: window ( N , wt )
// Description:
// Window generates a window function.
//
// N = length of desired window
// wt = window type desired
// "rect" = rectangular "tria" = triangular (Bartlett)
// "hann" = Hanning "hamm" = Hamming
// "blac" = Blackman
// Window returns a row vector containing samples of the desired
// window.
//---------------------------------------------------------------------------
window = function ( N, wt )
{
local (m, nn, pn, w)
nn = N-1;
pn = 2*pi*(0:nn)/nn;
if (wt == "rect")
{
w = ones (1, N);
else if (wt == "tria") {
m = nn/2;
w = (0:m)/m;
w = [w, w[ceil(m):1:-1]];
else if (wt == "hann") {
w = 0.5*(1 - cos (pn));
else if (wt == "hamm") {
w = .54 - .46*cos (pn);
else if (wt == "blac") {
w = .42 -.5*cos (pn) + .08*cos (2*pn);
else
disp("Incorrect Window type requested");
}}}}}
return w';
};