1DLA_GERCOND(L1A)PACK routine (version 3.2)                         DLA_GERCOND(1)
2
3
4

NAME

6       DLA_GERCOND  - DLA_GERCOND estimate the Skeel condition number of op(A)
7       * op2(C)  where op2 is determined by CMODE as follows  CMODE = 1 op2(C)
8       = C  CMODE = 0 op2(C) = I  CMODE = -1 op2(C) = inv(C)  The Skeel condi‐
9       tion number cond(A) = norminf( |inv(A)||A| )  is computed by  computing
10       scaling  factors  R such that  diag(R)*A*op2(C) is row equilibrated and
11       computing the standard  infinity-norm condition number
12

SYNOPSIS

14       DOUBLE PRECISION FUNCTION DLA_GERCOND ( TRANS, N,  A,  LDA,  AF,  LDAF,
15                        IPIV, CMODE, C, INFO, WORK, IWORK )
16
17           IMPLICIT     NONE
18
19           CHARACTER    TRANS
20
21           INTEGER      N, LDA, LDAF, INFO, CMODE
22
23           INTEGER      IPIV( * ), IWORK( * )
24
25           DOUBLE       PRECISION  A( LDA, * ), AF( LDAF, * ), WORK( * ), C( *
26                        )
27

PURPOSE

29          DLA_GERCOND estimates the Skeel condition number of op(A) * op2(C)
30          where op2 is determined by CMODE as follows
31          CMODE =  1    op2(C) = C
32          CMODE =  0    op2(C) = I
33          CMODE = -1    op2(C) = inv(C)
34          The Skeel condition number cond(A) = norminf( |inv(A)||A| )
35          is computed by computing scaling factors R such that
36          diag(R)*A*op2(C) is row equilibrated and computing the standard
37          infinity-norm condition number.
38

ARGUMENTS

40       WORK    DOUBLE PRECISION workspace of size 3*N, and
41
42       IWORK   INTEGER workspace of size N.
43
44
45
46    LAPACK routine (version 3.2) November 2008                  DLA_GERCOND(1)
Impressum