CHBCB
Copies a complex Hermitian band matrix stored in band Hermitian storage mode to a complex band matrix stored in band storage mode.
Required Arguments
A — Complex band Hermitian matrix of order N. (Input)
NUCA — Number of codiagonals in A. (Input)
B — Complex band matrix of order N containing a copy of A. (Output)
NLCB — Number of lower codiagonals in B. (Input)
NLCB must be at least as large as NUCA.
NUCB — Number of upper codiagonals in B. (Input)
NUCB must be at least as large as NUCA.
Optional Arguments
N — Order of the matrices A and B. (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).
FORTRAN 90 Interface
Generic: CALL CHBCB (A, NUCA, B, NLCB, NUCB [, …])
Specific: The specific interface names are S_CHBCB and D_CHBCB.
FORTRAN 77 Interface
Single: CALL CHBCB (N, A, LDA, NUCA, B, LDB, NLCB, NUCB)
Double: The double precision name is DCHBCB.
Description
The routine CSBRB copies a complex matrix A stored in Hermitian band mode to a matrix B stored in complex band mode. The lower codiagonals of B are filled using the values in the upper codiagonals of A.
Comments
Informational errors
Type | Code | Description |
|---|
3 | 1 | An element on the diagonal has a complex part that is near zero, the complex part is set to zero. |
4 | 1 | An element on the diagonal has a complex part that is not zero. |
Example
A complex Hermitian matrix of order 3 in band Hermitian storage mode with one upper codiagonal is copied to a complex matrix in band storage mode.
USE CHBCB_INT
USE WRCRN_INT
IMPLICIT NONE
! Declare variables
INTEGER LDA, LDB, N, NLCB, NUCA, NUCB
PARAMETER (N=3, NUCA=1, LDA=NUCA+1, NLCB=NUCA, NUCB=NUCA, &
LDB=NLCB+NUCB+1)
!
COMPLEX A(LDA,N), B(LDB,N)
! Set values for A (in band mode)
! A = ( 0.0+0.0i -1.0+1.0i -2.0+2.0i )
! ( 1.0+0.0i 1.0+0.0i 1.0+0.0i )
!
DATA A/(0.0,0.0), (1.0,0.0), (-1.0,1.0), (1.0,0.0), (-2.0,2.0), &
(1.0,0.0)/
! Copy a complex Hermitian band matrix
! to a complex band matrix
CALL CHBCB (A, NUCA, B, NLCB, NUCB)
! Print results
CALL WRCRN ('B', B)
END
Output
B
1 2 3
1 ( 0.000, 0.000) (-1.000, 1.000) (-2.000, 2.000)
2 ( 1.000, 0.000) ( 1.000, 0.000) ( 1.000, 0.000)
3 (-1.000,-1.000) (-2.000,-2.000) ( 0.000, 0.000)
Published date: 03/19/2020
Last modified date: 03/19/2020
