On the Behavior of the Residual in Conjugate Gradient Method
Teruyoshi Washizawa
DOI: 10.4236/am.2010.13025   PDF    HTML     5,244 Downloads   10,775 Views  


In conjugate gradient method, it is well known that the recursively computed residual differs from true one as the iteration proceeds in finite arithmetic. Some work have been devoted to analyze this behavior and to evaluate the lower and the upper bounds of the difference. This paper focuses on the behavior of these two kinds of residuals, especially their lower bounds caused by the loss of trailing digit, respectively.

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T. Washizawa, "On the Behavior of the Residual in Conjugate Gradient Method," Applied Mathematics, Vol. 1 No. 3, 2010, pp. 211-214. doi: 10.4236/am.2010.13025.

Conflicts of Interest

The authors declare no conflicts of interest.


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