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tomo/utils/gausswin.m

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+%GAUSSWIN Gaussian window. 
+% REPLAENEMENT OF THE MATLAB VERSION THAT OFTEN
+% FAILS DUE TO SOME DEPENDENCIES 
+%   GAUSSWIN(N) returns an N-point Gaussian window.
+%
+%   GAUSSWIN(N, ALPHA) returns the ALPHA-valued N-point Gaussian
+%   window.  ALPHA is defined as the reciprocal of the standard
+%   deviation and is a measure of the width of its Fourier Transform.
+%   As ALPHA increases, the width of the window will decrease. If omitted,
+%   ALPHA is 2.5.
+%
+%   EXAMPLE:
+%      N = 32;
+%      wvtool(gausswin(N));
+%
+%
+%   See also CHEBWIN, KAISER, TUKEYWIN, WINDOW.
+
+%   Reference:
+%     [1] fredric j. harris [sic], On the Use of Windows for Harmonic
+%         Analysis with the Discrete Fourier Transform, Proceedings of
+%         the IEEE, Vol. 66, No. 1, January 1978
+
+%   Copyright 1988-2013 The MathWorks, Inc.
+
+function w = gausswin(L, a)
+
+narginchk(1,2);
+
+% Default value for Alpha
+if nargin < 2 || isempty(a),
+    a = 2.5;
+end
+
+%Cast to enforce Precision Rules
+L = double(L); % data type of L is checked in check_order
+
+% Compute window according to [1]
+N = L-1;
+n = (0:N)'-N/2;
+w = exp(-(1/2)*(a*n/(N/2)).^2);
+
+
+end