sentences:  There are many different ways to define a Laplacian which have different mathematical interpretations, and so the clustering will also have different interpretations.The eigenvectors that are relevant are the ones that correspond to smallest several eigenvalues of the Laplacian except for the smallest eigenvalue which will have a value of 0.For computational efficiency, these eigenvectors are often computed as the eigenvectors corresponding to the largest several eigenvalues of a function of the Laplacian.