.TH "BLAS/SRC/chbmv.f" 3 "Version 3.12.0" "LAPACK" \" -*- nroff -*-
.ad l
.nh
.SH NAME
BLAS/SRC/chbmv.f
.SH SYNOPSIS
.br
.PP
.SS "Functions/Subroutines"

.in +1c
.ti -1c
.RI "subroutine \fBchbmv\fP (uplo, n, k, alpha, a, lda, x, incx, beta, y, incy)"
.br
.RI "\fBCHBMV\fP "
.in -1c
.SH "Function/Subroutine Documentation"
.PP 
.SS "subroutine chbmv (character uplo, integer n, integer k, complex alpha, complex, dimension(lda,*) a, integer lda, complex, dimension(*) x, integer incx, complex beta, complex, dimension(*) y, integer incy)"

.PP
\fBCHBMV\fP 
.PP
\fBPurpose:\fP
.RS 4

.PP
.nf
 CHBMV  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
           On entry, ALPHA specifies the scalar alpha\&.
.fi
.PP
.br
\fIA\fP 
.PP
.nf
          A is COMPLEX 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 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
           On entry, BETA specifies the scalar beta\&.
.fi
.PP
.br
\fIY\fP 
.PP
.nf
          Y is COMPLEX 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 \fBchbmv\&.f\fP\&.
.SH "Author"
.PP 
Generated automatically by Doxygen for LAPACK from the source code\&.