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arXiv 1606.09402math.NAcs.DCcs.DScs.NA
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固定精度低秩矩阵逼近的有效随机算法

Efficient Randomized Algorithms for the Fixed-Precision Low-Rank Matrix Approximation

Wenjian Yu, Yu Gu, Yaohang Li

摘要:

研究了低秩矩阵逼近的随机化算法,重点研究了固定精度问题和处理大型矩阵的计算效率。该算法是基于所谓的QB分解,其中Q是一个正交矩阵。首先,提出了一种计算Frobenius范数近似误差的机制,该机制使得对于大型和/或稀疏矩阵能够有效地进行自适应秩确定。它可以与任何QB形式的因式分解算法相结合,其中B的行是增量生成的。基于P. - G. Martinsson和S.沃罗宁,这导致了一个称为randQB EI的算法。然后,我们进一步修改算法,得到一个通过有效的算法,randQB FP,这是数学上等价于现有的randQB算法,也适用于固定精度的问题。特别地,在一定条件下,randQB FP可以作为计算前导奇异值的单遍算法。与大和/或稀疏的测试矩阵,我们已经经验验证了所提出的技术,表现出显着的加速比和内存节省块randQB算法的优点。我们还证明了由randQB FP导出的单遍算法比现有的单遍算法精确得多。并从风景图像和信息检索应用程序的数据,我们已经显示了所提出的算法的优势,自适应测距算法解决固定精度的问题。

英文摘要:

Randomized algorithms for low-rank matrix approximation are investigated, with the emphasis on the fixed-precision problem and computational efficiency for handling large matrices. The algorithms are based on the so-called QB factorization, where Q is an orthonormal matrix. Firstly, a mechanism for calculating the approximation error in Frobenius norm is proposed, which enables efficient adaptive rank determination for large and/or sparse matrix. It can be combined with any QB-form factorization algorithm in which B's rows are incrementally generated. Based on the blocked randQB algorithm by P.-G. Martinsson and S. Voronin, this results in an algorithm called randQB EI. Then, we further revise the algorithm to obtain a pass-efficient algorithm, randQB FP, which is mathematically equivalent to the existing randQB algorithms and also suitable for the fixed-precision problem. Especially, randQB FP can serve as a single-pass algorithm for calculating leading singular values, under certain condition. With large and/or sparse test matrices, we have empirically validated the merits of the proposed techniques, which exhibit remarkable speedup and memory saving over the blocked randQB algorithm. We have also demonstrated that the single-pass algorithm derived by randQB FP is much more accurate than an existing single-pass algorithm. And with data from a scenic image and an information retrieval application, we have shown the advantages of the proposed algorithms over the adaptive range finder algorithm for solving the fixed-precision problem.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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