question: void newEquation ( DF_LatticeCell lhs , DF_Operator operator , DF_LatticeCell op1 , DF_LatticeCell op2 , DF_LatticeCell op3 ) { DF_Equation eq = new DF_Equation ( lhs , operator , op1 , op2 , op3 ) ; equations . addGraphNode ( eq ) ; equations . addGraphNode ( lhs ) ; equations . addGraphNode ( op1 ) ; equations . addGraphNode ( op2 ) ; equations . addGraphNode ( op3 ) ; newEquations . add ( eq ) ; op1 . addUse ( eq ) ; op2 . addUse ( eq ) ; op3 . addUse ( eq ) ; lhs . addDef ( eq ) ; if ( EAGER && eq . evaluate ( ) ) changedCell ( lhs ) ; }
target:  Add an equation with three operands on the right-hand side.