1 files changed, 3 insertions, 0 deletions
diff --git a/lib/feature.rb b/lib/feature.rb
index 9deb199..b2bc1f5 100644
--- a/lib/feature.rb
+++ b/lib/feature.rb
@@ -29,6 +29,9 @@ module OpenTox
   # Feature for SMARTS fragments
   class Smarts < NominalFeature
     field :smarts, type: String 
+    def self.from_smarts smarts
+      self.find_or_create_by :smarts => smarts
+    end
   end
 
   # Feature for supervised fragments from Fminer algorithm