ARBRB
Adds two band matrices, both in band storage mode.
Required Arguments
A — N by N band matrix with NLCA lower codiagonals and NUCA upper codiagonals stored in band mode with dimension (NLCA + NUCA + 1) by N. (Input)
NLCA — Number of lower codiagonals of A. (Input)
NUCA — Number of upper codiagonals of A. (Input)
B — N by N band matrix with NLCB lower codiagonals and NUCB upper codiagonals stored in band mode with dimension (NLCB + NUCB + 1) by N. (Input)
NLCB — Number of lower codiagonals of B. (Input)
NUCB — Number of upper codiagonals of B. (Input)
C — N by N band matrix with NLCC lower codiagonals and NUCC upper codiagonals containing the sum A + B in band mode with dimension (NLCC + NUCC + 1) by N. (Output)
NLCC — Number of lower codiagonals of C. (Input)
NLCC must be at least as large as max(NLCA, NLCB).
NUCC — Number of upper codiagonals of C. (Input)
NUCC must be at least as large as max(NUCA, NUCB).
Optional Arguments
N — Order of the matrices A, B and C. (Input)
Default: N = SIZE (A,2).
LDA — Leading dimension of A exactly as specified in the dimension statement of the calling program. (Input)
Default: LDA = SIZE (A,1).
LDB — Leading dimension of B exactly as specified in the dimension statement of the calling program. (Input)
Default: LDB = SIZE (B,1).
LDC — Leading dimension of C exactly as specified in the dimension statement of the calling program. (Input)
Default: LDC = SIZE (C,1).
FORTRAN 90 Interface
Generic: CALL ARBRB (A, NLCA, NUCA, B, NLCB, NUCB, C, NLCC, NUCC [, …])
Specific: The specific interface names are S_ARBRB and D_ARBRB.
FORTRAN 77 Interface
Single: CALL ARBRB (N, A, LDA, NLCA, NUCA, B, LDB, NLCB, NUCB, C, LDC, NLCC, NUCC)
Double: The double precision name is DARBRB.
Description
The routine ARBRB adds two real matrices stored in band mode, returning a real matrix stored in band mode.
Example
Add two real matrices of order 4 stored in band mode. Matrix A has one upper codiagonal and one lower codiagonal. Matrix B has no upper codiagonals and two lower codiagonals. The output matrix C, has one upper codiagonal and two lower codiagonals.
USE ARBRB_INT
USE WRRRN_INT
IMPLICIT NONE
! Declare variables
INTEGER LDA, LDB, LDC, N, NLCA, NLCB, NLCC, NUCA, NUCB, NUCC
PARAMETER (LDA=3, LDB=3, LDC=4, N=4, NLCA=1, NLCB=2, NLCC=2, &
NUCA=1, NUCB=0, NUCC=1)
!
REAL A(LDA,N), B(LDB,N), C(LDC,N)
! Set values for A (in band mode)
! A = ( 0.0 2.0 3.0 -1.0)
! ( 1.0 1.0 1.0 1.0)
! ( 0.0 3.0 4.0 0.0)
!
! Set values for B (in band mode)
! B = ( 3.0 3.0 3.0 3.0)
! ( 1.0 -2.0 1.0 0.0)
! ( -1.0 2.0 0.0 0.0)
!
DATA A/0.0, 1.0, 0.0, 2.0, 1.0, 3.0, 3.0, 1.0, 4.0, -1.0, 1.0, &
0.0/
DATA B/3.0, 1.0, -1.0, 3.0, -2.0, 2.0, 3.0, 1.0, 0.0, 3.0, 0.0, &
0.0/
! Add A and B to obtain C (in band
! mode)
CALL ARBRB (A, NLCA, NUCA, B, NLCB, NUCB, C, NLCC, NUCC)
! Print results
CALL WRRRN ('C = A+B', C)
END
Output
C = A+B
1 2 3 4
1 0.000 2.000 3.000 -1.000
2 4.000 4.000 4.000 4.000
3 1.000 1.000 5.000 0.000
4 -1.000 2.000 0.000 0.000
