Difference between revisions of "Givens method"

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(Created page with " Primary authors of this description: A.V.Frolov, Vad.V.Voevodin (Section 2.2) 1 Properties and structure of the algorithm[edit] 1.1 General description of the algorithm...")
 
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1.1 General description of the algorithm  
 
1.1 General description of the algorithm  
  
'''Givens' method''' (which is also called '''the rotation method''' in the Russian mathematical literature) is used to represent a matrix in the form A = QR, where Q is a unitary and R is an upper triangular matrix. The matrix Q is not stored and used in its explicit form but rather as the product of rotations. Each (Givens) rotation can be specified by a pair of indices and a single parameter. In a conventional implementation of Givens' method
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'''Givens' method''' (which is also called '''the rotation method''' in the Russian mathematical literature) is used to represent a matrix in the form ''A = QR'', where ''Q'' is a unitary and ''R'' is an upper triangular matrix. The matrix Q is not stored and used in its explicit form but rather as the product of rotations. Each (Givens) rotation can be specified by a pair of indices and a single parameter. In a conventional implementation of Givens' method, this fact makes it possible to avoid using additional arrays by storing the results of decomposition in the array originally occupied by ''A''.

Revision as of 19:04, 21 January 2016


Primary authors of this description: A.V.Frolov, Vad.V.Voevodin (Section 2.2)


1 Properties and structure of the algorithm[edit] 1.1 General description of the algorithm

Givens' method (which is also called the rotation method in the Russian mathematical literature) is used to represent a matrix in the form A = QR, where Q is a unitary and R is an upper triangular matrix. The matrix Q is not stored and used in its explicit form but rather as the product of rotations. Each (Givens) rotation can be specified by a pair of indices and a single parameter. In a conventional implementation of Givens' method, this fact makes it possible to avoid using additional arrays by storing the results of decomposition in the array originally occupied by A.