163 SUBROUTINE slaed1( N, D, Q, LDQ, INDXQ, RHO, CUTPNT, WORK, IWORK,
172 INTEGER cutpnt, info, ldq, n
176 INTEGER indxq( * ), iwork( * )
177 REAL d( * ), q( ldq, * ), work( * )
183 INTEGER coltyp, cpp1, i, idlmda, indx, indxc, indxp,
184 $ iq2, is, iw, iz, k, n1, n2
200 ELSE IF( ldq.LT.max( 1, n ) )
THEN
202 ELSE IF( min( 1, n / 2 ).GT.cutpnt .OR. ( n / 2 ).LT.cutpnt )
THEN
206 CALL
xerbla(
'SLAED1', -info )
233 CALL
scopy( cutpnt, q( cutpnt, 1 ), ldq, work( iz ), 1 )
235 CALL
scopy( n-cutpnt, q( cpp1, cpp1 ), ldq, work( iz+cutpnt ), 1 )
239 CALL
slaed2( k, n, cutpnt, d, q, ldq, indxq, rho, work( iz ),
240 $ work( idlmda ), work( iw ), work( iq2 ),
241 $ iwork( indx ), iwork( indxc ), iwork( indxp ),
242 $ iwork( coltyp ), info )
250 is = ( iwork( coltyp )+iwork( coltyp+1 ) )*cutpnt +
251 $ ( iwork( coltyp+1 )+iwork( coltyp+2 ) )*( n-cutpnt ) + iq2
252 CALL
slaed3( k, n, cutpnt, d, q, ldq, rho, work( idlmda ),
253 $ work( iq2 ), iwork( indxc ), iwork( coltyp ),
254 $ work( iw ), work( is ), info )
262 CALL
slamrg( n1, n2, d, 1, -1, indxq )
subroutine slaed2(K, N, N1, D, Q, LDQ, INDXQ, RHO, Z, DLAMDA, W, Q2, INDX, INDXC, INDXP, COLTYP, INFO)
SLAED2 used by sstedc. Merges eigenvalues and deflates secular equation. Used when the original matri...
subroutine slamrg(N1, N2, A, STRD1, STRD2, INDEX)
SLAMRG creates a permutation list to merge the entries of two independently sorted sets into a single...
subroutine xerbla(SRNAME, INFO)
XERBLA
subroutine scopy(N, SX, INCX, SY, INCY)
SCOPY
subroutine slaed3(K, N, N1, D, Q, LDQ, RHO, DLAMDA, Q2, INDX, CTOT, W, S, INFO)
SLAED3 used by sstedc. Finds the roots of the secular equation and updates the eigenvectors. Used when the original matrix is tridiagonal.
subroutine slaed1(N, D, Q, LDQ, INDXQ, RHO, CUTPNT, WORK, IWORK, INFO)
SLAED1 used by sstedc. Computes the updated eigensystem of a diagonal matrix after modification by a ...