%==========================================================================
% window for time-frequency analysis
%==========================================================================

function w=win(y,width)

    %======================================================================
    % input
    %======================================================================
    
    s=width;      % variance = s*s/2
    
    %======================================================================
    % computation
    %======================================================================
    
    w=power(pi*s*s,-0.25)*exp(-0.5*y.*y/(s*s));