Figure 4From: Inferring chemical reaction patterns using rule composition in graph grammarsExample of (a) a match matrix and the same matrix with (b) its virtual extension. The top row specifies 1 possibility for L 2 1 ⊆ R 1 1 and 2 for L 2 1 ⊆ R 1 3 . The extended matrix further specifies that L 2 1 can be unmatched. The bottom rows can be interpreted similarly. We display the number of matchings instead of a representation of the matchings themselves.Back to article page