function [bonds,status] = zero_cause(bonds);
% zero_cause - causality for zero junctions
%
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% %%%%% Model Transformation Tools %%%%%
% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
% Matlab function zero_cause
% [bonds,status] = zero_cause(bonds);
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% %% Version control history
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% %% $Id$
% %% $Log$
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%Effort
[bonds,e_status] = juncause(bonds,1,1);
%Flow
[bonds,f_status] = juncause(bonds,1,-1);
status = 0;
if (e_status==1)|(f_status==1) % Over causal
status = 1;
endif;
if (e_status==-1)|(f_status==-1) % Under causal
status = -1;
endif;