disjunction_name IS IF term_condition THEN constraint_name_1; … constraint_name_i ; … constraint_name_n ; [ELSE]  [ELSIF term_condition THEN] constraint_name_n+1; … constraint_name_r; … constraint_name_z; ENDIF; 
$ONECHO > "%lm.info%" Disjunction D1, D2; D1 IS IF Y('1') THEN CONSTRAINT1; EQUATION1; ELSIF Y('2') THEN CONSTRAINT2; EQUATION2; ENDIF;< D2 IS IF Y('3') THEN CONSTRAINT3; ELSE CONSTRAINT4; ENDIF; $OFFECHO 
$ONECHO > "%lm.info%" Disjunction D(j); D(j) IS IF Y(j) THEN CONSTR1(j); CONSTR2(i,j); ELSE CONSTR3(j); CONSTR4(j,k); ENDIF; $OFFECHO 
$ONECHO > "%lm.info%" Disjunction D(j); D('1') IS IF Y('1') THEN CONSTR1('1'); CONSTR2('1','1'); CONSTR2('2','1'); CONSTR2('3','1'); ELSE CONSTR3('1'); CONSTR4('1','a'); CONSTR4('1','b'); ENDIF; D('2') IS IF Y('2') THEN CONSTR1('2'); CONSTR2('1','2'); CONSTR2('2','2'); CONSTR2('3','2'); ELSE CONSTR3('2'); CONSTR4('2','a'); CONSTR4('2','b'); ENDIF; $OFFECHO 
Relational operators:

Sets operators:


Logic operators: and, or.  Using subsets 