Figure 2.

8-neighbour directions for searching critical points and vector cosine similarity. The ideal critical point should have a GVF force pointing outward in its 8-neighbourhood.The cosine similarity defines the cosine angle between the vectors, with values between 0 and 1.

Guo et al. BMC Genomics 2010 11(Suppl 2):S13   doi:10.1186/1471-2164-11-S2-S13