[pyrat] Rework negation of formula w/o touching the driver.

No need to modify the driver because PyRAT handles stict inequality symbols.

src/printers/pyrat.ml

@@ -96,20 +96,24 @@ let rec negate_term info t =
     (* Negate float relational symbols. *)
     let ls_neg =
       if Term.ls_equal ls info.ls_rel_float.le
-         || Term.ls_equal ls info.ls_rel_float.lt
+      then info.ls_rel_float.gt
+      else if Term.ls_equal ls info.ls_rel_float.lt
       then info.ls_rel_float.ge
       else if Term.ls_equal ls info.ls_rel_float.ge
-              || Term.ls_equal ls info.ls_rel_float.gt
+      then info.ls_rel_float.lt
+      else if Term.ls_equal ls info.ls_rel_float.gt
       then info.ls_rel_float.le
       else ls
     in
     (* Negate real relational symbols. *)
     let ls_neg =
       if Term.ls_equal ls info.ls_rel_real.le
-         || Term.ls_equal ls info.ls_rel_real.lt
+      then info.ls_rel_real.gt
+      else if Term.ls_equal ls info.ls_rel_real.lt
       then info.ls_rel_real.ge
       else if Term.ls_equal ls info.ls_rel_real.ge
-              || Term.ls_equal ls info.ls_rel_real.gt
+      then info.ls_rel_real.lt
+      else if Term.ls_equal ls info.ls_rel_real.gt
       then info.ls_rel_real.le
       else ls_neg
     in