svds
(Package: RSpectra) :
Find the Largest k Singular Values/Vectors of a Matrix
Given an m by n matrix A, function svds() can find its largest k singular values and the corresponding singular vectors. It is also called the Truncated SVD or Partial SVD since it only calculates a subset of the whole singular triplets.
eigs
(Package: RSpectra) :
Find a Specified Number of Eigenvalues/vectors for Square Matrix
Given an n by n matrix A, function eigs() can calculate a limited number of eigenvalues and eigenvectors of A. Users can specify the selection criteria by argument which, e.g., choosing the k largest or smallest eigenvalues and the corresponding eigenvectors.
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