Accession Number : AD0785244

Title :   A Comparison of the PLU and QR Methods for Determining Eigenvalues of Real Hessenberg Matrices.

Descriptive Note : Final rept.,


Personal Author(s) : Panttaja,J. T.

Report Date : MAY 1974

Pagination or Media Count : 61

Abstract : The LU algorithm with interchanges (herein after PLU) should be substantially faster than the QR, based on an order n squared count of floating point arithmetic operations, and is essentially stable. If this comparison held in actual executions of these two algorithms, and if the PLU provided convergence on most matrices, it would be a strong case for using the PLU instead of QR. In actual timings of the algorithms on test matrices, the PLU algorithm did not yield as substantial a savings as was predicted by this traditional operation count. This anomaly is considered. (Modified author abstract)

Descriptors :   *Computer programming, *Matrices(Mathematics), Computations, Iterations, Algorithms

Subject Categories : Theoretical Mathematics
      Computer Programming and Software

Distribution Statement : APPROVED FOR PUBLIC RELEASE