PROGRAM LA_SGBSVX_ET_EXAMPLE ! ! -- LAPACK95 INTERFACE DRIVER ROUTINE (VERSION 3.0) -- ! UNI-C, DENMARK; UNIV. OF TENNESSEE, USA; NAG LTD., UK ! SEPTEMBER, 2000 ! ! .. USE STATEMENTS USE LA_PRECISION, ONLY: WP => SP USE F95_LAPACK, ONLY: LA_GBSVX ! .. IMPLICIT STATEMENT .. IMPLICIT NONE ! .. PARAMETERS .. CHARACTER(LEN=*), PARAMETER :: FMT = '(8(1X,F10.3))' INTEGER, PARAMETER :: NIN=5, NOUT=6 ! .. LOCAL SCALARS .. INTEGER :: K, KL, KU, I, J, INFO, N, NRHS ! .. LOCAL ARRAYS .. INTEGER, ALLOCATABLE :: IPIV(:) REAL(WP), ALLOCATABLE :: AA(:,:), BB(:,:) REAL(WP), ALLOCATABLE :: A(:,:), B(:,:), X(:,:) ! .. EXECUTABLE STATEMENTS .. WRITE (NOUT,*) 'SGBSVX ET_Example Program Results.' READ ( NIN, * ) ! SKIP HEADING IN DATA FILE READ ( NIN, * ) N, KL, KU, NRHS PRINT *, 'N = ', N, ' KL = ', KL, ' KU = ', KU, ' NRHS = ', NRHS ALLOCATE ( A(KL+KU+1,N), AA(KL+KU+1,N), B(N,NRHS), BB(N,NRHS), X(N,NRHS), IPIV(N) ) ! AA = HUGE(1.0_WP) DO I = 1, 1+KU READ (NIN, *) (AA(I, J), J = KU-I+2,N) ENDDO DO I = 2+KU, KL+KU+1 READ (NIN, *) (AA(I, J), J = 1, N-I+KU+1) ENDDO B = 0.0_WP DO I = 1, NRHS DO J = 1, N DO K = MAX(1,J-KL), MIN(J+KU,N) BB(J,I) = AA(KU+1+J-K,K) + BB(J,I) ENDDO ENDDO BB(:,I) = BB(:,I)*I ENDDO A=AA; B=BB WRITE(NOUT,*) 'The matrix A:' DO I = 1, KL+KU+1 WRITE (NOUT,*) 'I = ', I; WRITE (NOUT,FMT) A(I,:) ENDDO WRITE(NOUT,*) 'The RHS matrix B:' DO J = 1, NRHS WRITE (NOUT,*) 'RHS', J; WRITE (NOUT,FMT) B(:,J) ENDDO ! ! WRITE ( NOUT, * )'---------------------------------------------------------' WRITE ( NOUT, * ) WRITE ( NOUT, * )'Details of LA_SGBSVX LAPACK SUBROUTINE Results.' WRITE ( NOUT, * ) ! WRITE(NOUT,*) WRITE(NOUT,*) 'CALL LA_GBSVX( A, B, X, KL, IPIV=IPIV, INFO=INFO )' A=AA; B=BB CALL LA_GBSVX( A, B, X, KL, IPIV=IPIV, INFO=INFO ) WRITE(NOUT,*)' X - the solution vectors computed by LA_GBSVX, INFO = ', INFO DO J = 1, NRHS; WRITE (NOUT,FMT) X(:,J); END DO WRITE(NOUT,*) 'Pivots: ', IPIV WRITE(NOUT,*) WRITE(NOUT,*) 'CALL LA_GBSVX( A, B(1:N,1), X(1:N,1), KL, IPIV=IPIV, INFO=INFO )' A=AA; B=BB CALL LA_GBSVX( A, B(1:N,1), X(1:N,1), KL, IPIV=IPIV, INFO=INFO ) WRITE(NOUT,*)' X - the solution vectors computed by LA_GBSVX, INFO = ', INFO WRITE (NOUT,FMT) X(:,1) WRITE(NOUT,*) 'Pivots: ', IPIV ! WRITE(NOUT,*)' X - the solution vectors computed by LA_GBSVX:' WRITE(NOUT,*) WRITE(NOUT,*) 'CALL LA_GBSVX( A, B, X, KL )' A=AA; B=BB CALL LA_GBSVX( A, B, X, KL ) WRITE(NOUT,*)' X - the solution vectors computed by LA_GBSVX:' DO J = 1, NRHS; WRITE (NOUT,FMT) X(:,J); END DO WRITE(NOUT,*) WRITE(NOUT,*) 'CALL LA_GBSVX(A, B(1:N,1), X(1:N,1), KL)' A=AA; B=BB CALL LA_GBSVX(A, B(1:N,1), X(1:N,1), KL) WRITE(NOUT,*)' X - the solution vectors computed by LA_GBSVX:' WRITE (NOUT,FMT) X(:,1) ! WRITE(NOUT,*) WRITE(NOUT,*) 'CALL LA_GBSVX(A, B, X, IPIV=IPIV)' A=AA; B=BB CALL LA_GBSVX( A, B, X, IPIV=IPIV) WRITE(NOUT,*)' X - the solution vectors computed by LA_GBSVX:' DO J = 1, NRHS; WRITE (NOUT,FMT) X(:,J); END DO WRITE(NOUT,*) 'Pivots: ', IPIV WRITE(NOUT,*) WRITE(NOUT,*) 'CALL LA_GBSVX( A, B(1:N,1), X(1:N,1), IPIV=IPIV )' A=AA; B=BB CALL LA_GBSVX( A, B(1:N,1), X(1:N,1), IPIV=IPIV ) WRITE(NOUT,*)' X - the solution vectors computed by LA_GBSVX:' WRITE (NOUT,FMT) X(1:N,1) WRITE(NOUT,*) 'Pivots: ', IPIV ! WRITE(NOUT,*) WRITE(NOUT,*) 'CALL LA_GBSVX(A(4:4,:), B, X, INFO =INFO )' A=AA; B=BB; X=HUGE(1.0_WP) CALL LA_GBSVX( A(4:4,:), B, X, INFO=INFO) WRITE(NOUT,*)' X - the solution vectors computed by LA_GBSVX, INFO = ', INFO DO J = 1, NRHS; WRITE (NOUT,FMT) X(:,J); END DO WRITE(NOUT,*) WRITE(NOUT,*) 'CALL LA_GBSVX( A(4:4,:), B(1:N,1), X(1:N,1), INFO=INFO )' A=AA; B=BB; X=HUGE(1.0_WP) CALL LA_GBSVX( A(4:4,:), B(1:N,1), X(1:N,1), INFO=INFO ) WRITE(NOUT,*)' B - the RHS vector.' WRITE (NOUT,FMT) B(1:N,1) WRITE(NOUT,*)' X - the solution vectors computed by LA_GBSVX, INFO = ', INFO WRITE (NOUT,FMT) X(1:N,1) ! WRITE(NOUT,*) WRITE(NOUT,*) 'CALL LA_GBSVX(A(4:4,:), B, X, 1, INFO =INFO )' A=AA; B=BB; X=HUGE(1.0_WP) CALL LA_GBSVX( A(4:4,:), B, X, 1, INFO=INFO) WRITE(NOUT,*)' INFO = ', INFO ! WRITE(NOUT,*) WRITE(NOUT,*) 'CALL LA_GBSVX(A(4:4,:), B, X, 6, INFO =INFO )' A=AA; B=BB; X=HUGE(1.0_WP) CALL LA_GBSVX( A(4:4,:), B, X, 1, INFO=INFO) WRITE(NOUT,*)' INFO = ', INFO ! WRITE(NOUT,*) WRITE(NOUT,*) 'CALL LA_GBSVX( A, B(1:N,1), X(1:N,1), 1, INFO=INFO )' A=AA; B=BB; X=HUGE(1.0_WP) CALL LA_GBSVX( A, B(1:N,1), X(1:N,1), 6, INFO=INFO ) WRITE(NOUT,*)' INFO = ', INFO ! WRITE(NOUT,*) WRITE(NOUT,*) 'CALL LA_GBSVX( A, B(1:N,1), X(1:N,1), 6 )' A=AA; B=BB; X=HUGE(1.0_WP) CALL LA_GBSVX( A, B(1:N,1), X(1:N,1), 6 ) WRITE(NOUT,*)' INFO = ', INFO ! END PROGRAM LA_SGBSVX_ET_EXAMPLE