There are two cases (B) and (C) after normalizing by the maximum value max(x, a, b) in (A). In (B), the maximum value is x = 1 after normalization. SF is defined by a + b = 1. In (C), the maximum value is b = 1 after normalization. CF and NF are defined by 1 + a = 2x and x = a, x ≤ 0.5, respectively.
Zeng and Hannenhalli BMC Genomics 2013 14(Suppl 1):S15 doi:10.1186/1471-2164-14-S1-S15