##### Department of Mathematics,

University of California San Diego

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### Center for Computational Mathematics Seminar

## Xin Liu

#### Chinese Academy of Sciences

## Limited Memory Subspace Acceleration for Computing Dominant Singular Values and Vectors

##### Abstract:

\indent Many data-related applications utilize principal component analysis and/or data dimension reduction techniques that require efficiently computing dominant part of singular value decompositions (SVD) of very large matrices which are also very dense. In our talk, we introduce a limited memory block krylov subspace optimization method which remarkablely accelerate the traditional simultaneous iteration scheme. We present extensive numerical results comparing the algorithm with some state-of-the-art SVD solvers. Our tests indicate that the proposed method can provide better performance over a range of dense problem classes under the MATLAB environment. We also present some convergence properties of our algorithm.

### April 5, 2011

### 11:00 AM

### AP&M 2402

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