--- rpl/lapack/lapack/dlansb.f 2020/05/21 21:45:59 1.18 +++ rpl/lapack/lapack/dlansb.f 2023/08/07 08:38:55 1.19 @@ -121,20 +121,16 @@ *> \author Univ. of Colorado Denver *> \author NAG Ltd. * -*> \date December 2016 -* *> \ingroup doubleOTHERauxiliary * * ===================================================================== DOUBLE PRECISION FUNCTION DLANSB( NORM, UPLO, N, K, AB, LDAB, $ WORK ) * -* -- LAPACK auxiliary routine (version 3.7.0) -- +* -- LAPACK auxiliary routine -- * -- LAPACK is a software package provided by Univ. of Tennessee, -- * -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..-- -* December 2016 * - IMPLICIT NONE * .. Scalar Arguments .. CHARACTER NORM, UPLO INTEGER K, LDAB, N @@ -151,18 +147,15 @@ * .. * .. Local Scalars .. INTEGER I, J, L - DOUBLE PRECISION ABSA, SUM, VALUE + DOUBLE PRECISION ABSA, SCALE, SUM, VALUE * .. -* .. Local Arrays .. - DOUBLE PRECISION SSQ( 2 ), COLSSQ( 2 ) +* .. External Subroutines .. + EXTERNAL DLASSQ * .. * .. External Functions .. LOGICAL LSAME, DISNAN EXTERNAL LSAME, DISNAN * .. -* .. External Subroutines .. - EXTERNAL DLASSQ, DCOMBSSQ -* .. * .. Intrinsic Functions .. INTRINSIC ABS, MAX, MIN, SQRT * .. @@ -229,47 +222,29 @@ ELSE IF( ( LSAME( NORM, 'F' ) ) .OR. ( LSAME( NORM, 'E' ) ) ) THEN * * Find normF(A). -* SSQ(1) is scale -* SSQ(2) is sum-of-squares -* For better accuracy, sum each column separately. -* - SSQ( 1 ) = ZERO - SSQ( 2 ) = ONE -* -* Sum off-diagonals * + SCALE = ZERO + SUM = ONE IF( K.GT.0 ) THEN IF( LSAME( UPLO, 'U' ) ) THEN DO 110 J = 2, N - COLSSQ( 1 ) = ZERO - COLSSQ( 2 ) = ONE CALL DLASSQ( MIN( J-1, K ), AB( MAX( K+2-J, 1 ), J ), - $ 1, COLSSQ( 1 ), COLSSQ( 2 ) ) - CALL DCOMBSSQ( SSQ, COLSSQ ) + $ 1, SCALE, SUM ) 110 CONTINUE L = K + 1 ELSE DO 120 J = 1, N - 1 - COLSSQ( 1 ) = ZERO - COLSSQ( 2 ) = ONE - CALL DLASSQ( MIN( N-J, K ), AB( 2, J ), 1, - $ COLSSQ( 1 ), COLSSQ( 2 ) ) - CALL DCOMBSSQ( SSQ, COLSSQ ) + CALL DLASSQ( MIN( N-J, K ), AB( 2, J ), 1, SCALE, + $ SUM ) 120 CONTINUE L = 1 END IF - SSQ( 2 ) = 2*SSQ( 2 ) + SUM = 2*SUM ELSE L = 1 END IF -* -* Sum diagonal -* - COLSSQ( 1 ) = ZERO - COLSSQ( 2 ) = ONE - CALL DLASSQ( N, AB( L, 1 ), LDAB, COLSSQ( 1 ), COLSSQ( 2 ) ) - CALL DCOMBSSQ( SSQ, COLSSQ ) - VALUE = SSQ( 1 )*SQRT( SSQ( 2 ) ) + CALL DLASSQ( N, AB( L, 1 ), LDAB, SCALE, SUM ) + VALUE = SCALE*SQRT( SUM ) END IF * DLANSB = VALUE