Update smt2_commands.h

update comments

src/frontend/smt2/smt2_commands.h

@@ -290,9 +290,9 @@ typedef struct smt2_cmd_stats_s {
  *   occur after a (push ..) command are removed by the matching (pop ..).
  *   In global mode, declarations are kept independent of (push ..) and (pop ...)
  *   global_decls is false by default.
- * - clean_model_format is true by default. This flag determines how models
- *   are displayed in (get-model). The default is to use a Yices-style
- *   format. If the flag is false, we use the SMT2-style format (not clean!).
+ * - clean_model_format is false by default. This flag determines how models
+ *   are displayed in (get-model). If the flag is false, we use the SMT2-style
+ *.  format (not clean!). Otherwise, we use the Yices-style format.
  * - bvconst_in_decimal is false by default. This flag determines how bit-vector
  *   constants are displayed in (get-model) and (get-value ..>). If the flag
  *   is true, we print them in decimal otherwise, we print them in binary.