function diff=calcDiffSimp(busType,vsp2,Y,pVec,qVec,Vx)
% Calculate mismatch of simple power flow
% Author: Rui Yao <ruiyao@ieee.org>
%
% Copyright (C) 2021, UChicago Argonne, LLC. All rights reserved.
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% ***************************************************************************************************
%
diff=zeros(3*size(busType,1),size(Vx,2));
for i=1:size(Vx,2)
    V=Vx(:,i);
    qVecx=qVec;
    diffS=(pVec+1j*qVecx)-V.*conj(Y*V);
    diffP=real(diffS);
    diffQ=imag(diffS);
    diffP(busType==2)=0;
    diffQ(busType~=0)=0;
    diffV=vsp2-V.*conj(V);
    diffV(busType==0)=0;
    diff(:,i)=[diffP;diffQ;diffV];
end
end