function x0 = secondary_source_tapering(x0,conf)
%SECONDARY_SOURCE_TAPERING applies a tapering window to the secondary sources
%
%   Usage: x0 = secondary_source_tapering(x0,conf)
%
%   Input parameters:
%       x0          - secondary sources / m
%       conf        - configuration struct (see SFS_config)
%
%   Output parameters:
%       x0          - secondary sources / m, containing the applied tapering
%                     window in its weights in x0(:,7)
%
%   SECONDARY_SOURCE_TAPERING(x0,conf) applies a tapering window (depending on
%   the conf.usetapwin and conf.tapwinlen settings) to the secondary sources.
%   It is applied to the weights stored in x0(:,7).
%
%   See also: secondary_source_positions, tapering_window

%*****************************************************************************
% The MIT License (MIT)                                                      *
%                                                                            *
% Copyright (c) 2010-2019 SFS Toolbox Developers                             *
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% Permission is hereby granted,  free of charge,  to any person  obtaining a *
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% The SFS Toolbox  allows to simulate and  investigate sound field synthesis *
% methods like wave field synthesis or higher order ambisonics.              *
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%*****************************************************************************


%% ===== Checking of input  parameters ==================================
nargmin = 2;
nargmax = 2;
narginchk(nargmin,nargmax);


%% ===== Calculation ====================================================
% Apply tapering window to secondary sources
x0(:,7) = x0(:,7) .* tapering_window(x0,conf);
