ZQRT14 checks whether X is in the row space of A or A'.  It does so


 by scaling both X and A such that their norms are in the range


 [sqrt(eps), 1/sqrt(eps)], then computing a QR factorization of [A,X]


 (if TRANS = 'C') or an LQ factorization of [A',X]' (if TRANS = 'N'),


 and returning the norm of the trailing triangle, scaled by


 MAX(M,N,NRHS)*eps.

TRANS

          TRANS is CHARACTER*1


          = 'N':  No transpose, check for X in the row space of A


          = 'C':  Conjugate transpose, check for X in row space of A'.

M

          M is INTEGER


          The number of rows of the matrix A.

N

          N is INTEGER


          The number of columns of the matrix A.

NRHS

          NRHS is INTEGER


          The number of right hand sides, i.e., the number of columns


          of X.

A

          A is COMPLEX*16 array, dimension (LDA,N)


          The M-by-N matrix A.

LDA

          LDA is INTEGER


          The leading dimension of the array A.

X

          X is COMPLEX*16 array, dimension (LDX,NRHS)


          If TRANS = 'N', the N-by-NRHS matrix X.


          IF TRANS = 'C', the M-by-NRHS matrix X.

LDX

          LDX is INTEGER


          The leading dimension of the array X.

WORK

          WORK is COMPLEX*16 array dimension (LWORK)

LWORK

          LWORK is INTEGER


          length of workspace array required


          If TRANS = 'N', LWORK >= (M+NRHS)*(N+2);


          if TRANS = 'C', LWORK >= (N+NRHS)*(M+2).

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