hjc888老品牌黄金城学术报告
A flexible block classical Gram-Schmidt skeleton with reorthogonalization
邹秦萌
(北京邮电大学理学院)
报告时间:2023年3月10日 星期五 下午15:00-16:00
报告地点:北京航空航天大学 沙河校区 E404
报告摘要:We investigate a variant of the reorthogonalized block classical Gram-Schmidt method for computing the QR factorization of a full column rank matrix. Our aim is to bound the loss of orthogonality even when the first local QR algorithm is only conditionally stable. In particular, this allows the use of modified Gram-Schmidt instead of Householder transformations as the first local QR algorithm. Numerical experiments confirm the stable behavior of the new variant. We also examine the use of non-QR local factorization and show by example that the resulting variants, although less stable, may also be applied to ill-conditioned problems.
报告人简介:邹秦萌,北京航空航天大学学士、硕士,巴黎萨克雷大学博士、博士后,现为北京邮电大学副教授,研究方向为数值代数。
邀请人:谢家新