gaussian(x,iq,varargin)

%GAUSSIAN Evaluate an inverse Q parameter.
%
% GAUSSIAN(X,IQ,K) Evaluates a gaussian as a function of its inverse Q
% parameter, spatial position and wavenumber K.
%
% GAUSSIAN(X,IQ) As above, assuming K=1.
%
%See also: WR2IQ, IQ2WR, IQ2IQ

% $Author: graceej $ $Date: 2009/10/24 11:08:05 $
% $Revision: 1.7 $


% Copyright (c) 2009, Edward J. Grace
% All rights reserved.
 
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%       provided with the distribution.
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function u = gaussian(x,iq,varargin)
k=1;
if nargin>2
    k=varargin{1};
end
u=conj(sqrt(iq).*exp(-0.5.*i.*k.*iq.*x.^2));

%
% $Log: gaussian.m,v $
% Revision 1.7  2009/10/24 11:08:05  graceej
% * Modified license to make use of the current BSD style open source initiative license.
%
% Revision 1.6  2009/05/06 20:09:45  graceej
% * Updated make package target to include distribution of the license file and README.
%
% Revision 1.5  2009/04/20 13:36:18  graceej
% * Corrected for implicit -i omega t time convention.
%
% Revision 1.4  2009/04/20 12:58:44  graceej
% * Corrected for implicit -i omega t time convention.
%
% Revision 1.3  2009/04/19 19:03:49  graceej
% * Reworked gaussian ray transfer matrix code.
% * Corrected minor bugs in demos, using the old field for sampling rather than the newly propagated field.
%
% Revision 1.2  2009/04/18 18:24:45  graceej
% * Rationalised q parameter and gaussian related stuff.
%
%