TESTING/MATGEN/dlatm6.f(3)

NAME
TESTING/MATGEN/dlatm6.f

SYNOPSIS

  Functions/Subroutines
subroutine dlatm6 (type, n, a, lda, b, x, ldx, y, ldy, alpha, beta, wx, wy, s, dif)
DLATM6

Function/Subroutine Documentation

  subroutine dlatm6 (integer type, integer n, double precision, dimension( lda, * ) a, integer lda, double precision, dimension( lda, * ) b, double precision, dimension( ldx, * ) x, integer ldx, double precision, dimension( ldy, * ) y, integer ldy, double precision alpha, double precision beta, double precision wx, double precision wy, double precision, dimension( * ) s, double precision, dimension( * ) dif)

DLATM6

Purpose:

     DLATM6 generates test matrices for the generalized eigenvalue
     problem, their corresponding right and left eigenvector matrices,
     and also reciprocal condition numbers for all eigenvalues and
     the reciprocal condition numbers of eigenvectors corresponding to
     the 1th and 5th eigenvalues.
     Test Matrices
     =============
     Two kinds of test matrix pairs
           (A, B) = inverse(YH) * (Da, Db) * inverse(X)
     are used in the tests:
     Type 1:
        Da = 1+a   0    0    0    0    Db = 1   0   0   0   0
              0   2+a   0    0    0         0   1   0   0   0
              0    0   3+a   0    0         0   0   1   0   0
              0    0    0   4+a   0         0   0   0   1   0
              0    0    0    0   5+a ,      0   0   0   0   1 , and
     Type 2:
        Da =  1   -1    0    0    0    Db = 1   0   0   0   0
              1    1    0    0    0         0   1   0   0   0
              0    0    1    0    0         0   0   1   0   0
              0    0    0   1+a  1+b        0   0   0   1   0
              0    0    0  -1-b  1+a ,      0   0   0   0   1 .
     In both cases the same inverse(YH) and inverse(X) are used to compute
     (A, B), giving the exact eigenvectors to (A,B) as (YH, X):
     YH:  =  1    0   -y    y   -y    X =  1   0  -x  -x   x
             0    1   -y    y   -y         0   1   x  -x  -x
             0    0    1    0    0         0   0   1   0   0
             0    0    0    1    0         0   0   0   1   0
             0    0    0    0    1,        0   0   0   0   1 ,
     where a, b, x and y will have all values independently of each other.

Parameters
    TYPE

              TYPE is INTEGER
              Specifies the problem type (see further details).

    N

              N is INTEGER
              Size of the matrices A and B.

    A

              A is DOUBLE PRECISION array, dimension (LDA, N).
              On exit A N-by-N is initialized according to TYPE.

    LDA

              LDA is INTEGER
              The leading dimension of A and of B.

    B

              B is DOUBLE PRECISION array, dimension (LDA, N).
              On exit B N-by-N is initialized according to TYPE.

    X

              X is DOUBLE PRECISION array, dimension (LDX, N).
              On exit X is the N-by-N matrix of right eigenvectors.

    LDX

              LDX is INTEGER
              The leading dimension of X.

    Y

              Y is DOUBLE PRECISION array, dimension (LDY, N).
              On exit Y is the N-by-N matrix of left eigenvectors.

    LDY

              LDY is INTEGER
              The leading dimension of Y.

    ALPHA

              ALPHA is DOUBLE PRECISION

    BETA

              BETA is DOUBLE PRECISION
              Weighting constants for matrix A.

    WX

              WX is DOUBLE PRECISION
              Constant for right eigenvector matrix.

    WY

              WY is DOUBLE PRECISION
              Constant for left eigenvector matrix.

    S

              S is DOUBLE PRECISION array, dimension (N)
              S(i) is the reciprocal condition number for eigenvalue i.

    DIF

              DIF is DOUBLE PRECISION array, dimension (N)
              DIF(i) is the reciprocal condition number for eigenvector i.

Author
    Univ. of Tennessee

    Univ. of California Berkeley

    Univ. of Colorado Denver

    NAG Ltd.

Definition at line 174 of file dlatm6.f.

Author

Generated automatically by Doxygen for LAPACK from the source code.