The Mailman Algorithm: A Note on Matrix Vector Multiplication
Abstract
Given an m x n matrix A we are interested in applying it to a real vector x epsilon Rn in less then the straightforward O(mn) time. For an exact, deterministic computation at the very least all entrees in A must be accessed, requiring O(mn) operations and matching the running time of naively applying A to x. However, we claim that if the matrix contains only a constant number of distinct values, then reading the matrix once in O(mn) steps is sufficient to preprocess it such that any subsequent application to vectors requires only O(mn= log(max{m,ng}) operations. Theoretically our algorithm can improve on recent results for dimensionality reduction and practically it is useful (faster) even for small matrices.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 2008
- Accession Number
- ADA482124
Entities
People
- Edo Liberty
- Steven W. Zucker
Organizations
- Yale University