1. Quadratic Shape Descriptors. Rapid Superposition of Dissimilar Molecules Using Geometrically Invariant Surface Descriptors Goldman BB, Wipke WT. Quadratic Shape Descriptors. 1. Rapid Superposition of Dissimilar Molecules Using Geometrically Invariant Surface Descriptors.J. Chem. Inf. Comput. Sci., 40 (3), 644 -658, 2000 Goldman BB, Wipke WT. QSD quadratic shape descriptors. 2. Molecular docking using quadratic shape descriptors (QSDock).Proteins. 2000 Jan 1;38(1):79-94.

2. Hessian matrix or the Second Fundamental form of the surface patch The local range curvatures and directions of the surface patch are the eigenvalues and eigenvectors, respectively, of the II matrix.

3. w(u,v) ~

4. Let ( min, min ) and ( max, max ) represent the local range curvatures and directions of the surface patch, where min max and min, max are the eigenvectors associated with the eigenvalues min and max, respectively.

7. Shape Index

8. Shapes that are identical will have a similarity score of 1.0, and shapes that are exactly opposite will receive a score of 0.

9. Preprocessing time and space complexity is linear in the number of critical points