indicate optional param in elastic net
diff --git a/src/ports/postgres/modules/elastic_net/elastic_net.sql_in b/src/ports/postgres/modules/elastic_net/elastic_net.sql_in
index 157851d..c1aaebf 100644
--- a/src/ports/postgres/modules/elastic_net/elastic_net.sql_in
+++ b/src/ports/postgres/modules/elastic_net/elastic_net.sql_in
@@ -163,7 +163,7 @@
<DT>max_iter (optional)</DT>
<DD>INTEGER, default: 1000. The maximum number of iterations allowed.</DD>
-<DT>tolerance</DT>
+<DT>tolerance (optional)</DT>
<DD>FLOAT8, default: 1e-6. This is the criterion to stop iterating. Both the
'fista' and 'igd' optimizers compute the difference between the
log likelihood of two consecutive iterations, and when the difference is smaller
