LAPACK  3.5.0
LAPACK: Linear Algebra PACKage
 All Classes Files Functions Variables Typedefs Macros
cqrt11.f File Reference

Go to the source code of this file.

Functions/Subroutines

real function cqrt11 (M, K, A, LDA, TAU, WORK, LWORK)
 CQRT11 More...
 

Function/Subroutine Documentation

real function cqrt11 ( integer  M,
integer  K,
complex, dimension( lda, * )  A,
integer  LDA,
complex, dimension( * )  TAU,
complex, dimension( lwork )  WORK,
integer  LWORK 
)

CQRT11

Purpose:
 CQRT11 computes the test ratio

       || Q'*Q - I || / (eps * m)

 where the orthogonal matrix Q is represented as a product of
 elementary transformations.  Each transformation has the form

    H(k) = I - tau(k) v(k) v(k)'

 where tau(k) is stored in TAU(k) and v(k) is an m-vector of the form
 [ 0 ... 0 1 x(k) ]', where x(k) is a vector of length m-k stored
 in A(k+1:m,k).
Parameters
[in]M
          M is INTEGER
          The number of rows of the matrix A.
[in]K
          K is INTEGER
          The number of columns of A whose subdiagonal entries
          contain information about orthogonal transformations.
[in]A
          A is COMPLEX array, dimension (LDA,K)
          The (possibly partial) output of a QR reduction routine.
[in]LDA
          LDA is INTEGER
          The leading dimension of the array A.
[in]TAU
          TAU is COMPLEX array, dimension (K)
          The scaling factors tau for the elementary transformations as
          computed by the QR factorization routine.
[out]WORK
          WORK is COMPLEX array, dimension (LWORK)
[in]LWORK
          LWORK is INTEGER
          The length of the array WORK.  LWORK >= M*M + M.
Author
Univ. of Tennessee
Univ. of California Berkeley
Univ. of Colorado Denver
NAG Ltd.
Date
November 2011

Definition at line 99 of file cqrt11.f.

Here is the call graph for this function:

Here is the caller graph for this function: