.TH "BLAS/SRC/zhbmv.f" 3 "Version 3.12.0" "LAPACK" \" -*- nroff -*- .ad l .nh .SH NAME BLAS/SRC/zhbmv.f .SH SYNOPSIS .br .PP .SS "Functions/Subroutines" .in +1c .ti -1c .RI "subroutine \fBzhbmv\fP (uplo, n, k, alpha, a, lda, x, incx, beta, y, incy)" .br .RI "\fBZHBMV\fP " .in -1c .SH "Function/Subroutine Documentation" .PP .SS "subroutine zhbmv (character uplo, integer n, integer k, complex*16 alpha, complex*16, dimension(lda,*) a, integer lda, complex*16, dimension(*) x, integer incx, complex*16 beta, complex*16, dimension(*) y, integer incy)" .PP \fBZHBMV\fP .PP \fBPurpose:\fP .RS 4 .PP .nf !> !> ZHBMV performs the matrix-vector operation !> !> y := alpha*A*x + beta*y, !> !> where alpha and beta are scalars, x and y are n element vectors and !> A is an n by n hermitian band matrix, with k super-diagonals\&. !> .fi .PP .RE .PP \fBParameters\fP .RS 4 \fIUPLO\fP .PP .nf !> UPLO is CHARACTER*1 !> On entry, UPLO specifies whether the upper or lower !> triangular part of the band matrix A is being supplied as !> follows: !> !> UPLO = 'U' or 'u' The upper triangular part of A is !> being supplied\&. !> !> UPLO = 'L' or 'l' The lower triangular part of A is !> being supplied\&. !> .fi .PP .br \fIN\fP .PP .nf !> N is INTEGER !> On entry, N specifies the order of the matrix A\&. !> N must be at least zero\&. !> .fi .PP .br \fIK\fP .PP .nf !> K is INTEGER !> On entry, K specifies the number of super-diagonals of the !> matrix A\&. K must satisfy 0 \&.le\&. K\&. !> .fi .PP .br \fIALPHA\fP .PP .nf !> ALPHA is COMPLEX*16 !> On entry, ALPHA specifies the scalar alpha\&. !> .fi .PP .br \fIA\fP .PP .nf !> A is COMPLEX*16 array, dimension ( LDA, N ) !> Before entry with UPLO = 'U' or 'u', the leading ( k + 1 ) !> by n part of the array A must contain the upper triangular !> band part of the hermitian matrix, supplied column by !> column, with the leading diagonal of the matrix in row !> ( k + 1 ) of the array, the first super-diagonal starting at !> position 2 in row k, and so on\&. The top left k by k triangle !> of the array A is not referenced\&. !> The following program segment will transfer the upper !> triangular part of a hermitian band matrix from conventional !> full matrix storage to band storage: !> !> DO 20, J = 1, N !> M = K + 1 - J !> DO 10, I = MAX( 1, J - K ), J !> A( M + I, J ) = matrix( I, J ) !> 10 CONTINUE !> 20 CONTINUE !> !> Before entry with UPLO = 'L' or 'l', the leading ( k + 1 ) !> by n part of the array A must contain the lower triangular !> band part of the hermitian matrix, supplied column by !> column, with the leading diagonal of the matrix in row 1 of !> the array, the first sub-diagonal starting at position 1 in !> row 2, and so on\&. The bottom right k by k triangle of the !> array A is not referenced\&. !> The following program segment will transfer the lower !> triangular part of a hermitian band matrix from conventional !> full matrix storage to band storage: !> !> DO 20, J = 1, N !> M = 1 - J !> DO 10, I = J, MIN( N, J + K ) !> A( M + I, J ) = matrix( I, J ) !> 10 CONTINUE !> 20 CONTINUE !> !> Note that the imaginary parts of the diagonal elements need !> not be set and are assumed to be zero\&. !> .fi .PP .br \fILDA\fP .PP .nf !> LDA is INTEGER !> On entry, LDA specifies the first dimension of A as declared !> in the calling (sub) program\&. LDA must be at least !> ( k + 1 )\&. !> .fi .PP .br \fIX\fP .PP .nf !> X is COMPLEX*16 array, dimension at least !> ( 1 + ( n - 1 )*abs( INCX ) )\&. !> Before entry, the incremented array X must contain the !> vector x\&. !> .fi .PP .br \fIINCX\fP .PP .nf !> INCX is INTEGER !> On entry, INCX specifies the increment for the elements of !> X\&. INCX must not be zero\&. !> .fi .PP .br \fIBETA\fP .PP .nf !> BETA is COMPLEX*16 !> On entry, BETA specifies the scalar beta\&. !> .fi .PP .br \fIY\fP .PP .nf !> Y is COMPLEX*16 array, dimension at least !> ( 1 + ( n - 1 )*abs( INCY ) )\&. !> Before entry, the incremented array Y must contain the !> vector y\&. On exit, Y is overwritten by the updated vector y\&. !> .fi .PP .br \fIINCY\fP .PP .nf !> INCY is INTEGER !> On entry, INCY specifies the increment for the elements of !> Y\&. INCY must not be zero\&. !> .fi .PP .RE .PP \fBAuthor\fP .RS 4 Univ\&. of Tennessee .PP Univ\&. of California Berkeley .PP Univ\&. of Colorado Denver .PP NAG Ltd\&. .RE .PP \fBFurther Details:\fP .RS 4 .PP .nf !> !> Level 2 Blas routine\&. !> The vector and matrix arguments are not referenced when N = 0, or M = 0 !> !> -- Written on 22-October-1986\&. !> Jack Dongarra, Argonne National Lab\&. !> Jeremy Du Croz, Nag Central Office\&. !> Sven Hammarling, Nag Central Office\&. !> Richard Hanson, Sandia National Labs\&. !> .fi .PP .RE .PP .PP Definition at line \fB186\fP of file \fBzhbmv\&.f\fP\&. .SH "Author" .PP Generated automatically by Doxygen for LAPACK from the source code\&.