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

.in +1c
.ti -1c
.RI "subroutine \fBstbmv\fP (uplo, trans, diag, n, k, a, lda, x, incx)"
.br
.RI "\fBSTBMV\fP "
.in -1c
.SH "Function/Subroutine Documentation"
.PP 
.SS "subroutine stbmv (character uplo, character trans, character diag, integer n, integer k, real, dimension(lda,*) a, integer lda, real, dimension(*) x, integer incx)"

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

.PP
.nf
!>
!> STBMV  performs one of the matrix-vector operations
!>
!>    x := A*x,   or   x := A**T*x,
!>
!> where x is an n element vector and  A is an n by n unit, or non-unit,
!> upper or lower triangular band matrix, with ( k + 1 ) diagonals\&.
!> 
.fi
.PP
 
.RE
.PP
\fBParameters\fP
.RS 4
\fIUPLO\fP 
.PP
.nf
!>          UPLO is CHARACTER*1
!>           On entry, UPLO specifies whether the matrix is an upper or
!>           lower triangular matrix as follows:
!>
!>              UPLO = 'U' or 'u'   A is an upper triangular matrix\&.
!>
!>              UPLO = 'L' or 'l'   A is a lower triangular matrix\&.
!> 
.fi
.PP
.br
\fITRANS\fP 
.PP
.nf
!>          TRANS is CHARACTER*1
!>           On entry, TRANS specifies the operation to be performed as
!>           follows:
!>
!>              TRANS = 'N' or 'n'   x := A*x\&.
!>
!>              TRANS = 'T' or 't'   x := A**T*x\&.
!>
!>              TRANS = 'C' or 'c'   x := A**T*x\&.
!> 
.fi
.PP
.br
\fIDIAG\fP 
.PP
.nf
!>          DIAG is CHARACTER*1
!>           On entry, DIAG specifies whether or not A is unit
!>           triangular as follows:
!>
!>              DIAG = 'U' or 'u'   A is assumed to be unit triangular\&.
!>
!>              DIAG = 'N' or 'n'   A is not assumed to be unit
!>                                  triangular\&.
!> 
.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 with UPLO = 'U' or 'u', K specifies the number of
!>           super-diagonals of the matrix A\&.
!>           On entry with UPLO = 'L' or 'l', K specifies the number of
!>           sub-diagonals of the matrix A\&.
!>           K must satisfy  0 \&.le\&. K\&.
!> 
.fi
.PP
.br
\fIA\fP 
.PP
.nf
!>          A is REAL 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 matrix of coefficients, 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 an upper
!>           triangular 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 matrix of coefficients, 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 a lower
!>           triangular 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 when DIAG = 'U' or 'u' the elements of the array A
!>           corresponding to the diagonal elements of the matrix are not
!>           referenced, but are assumed to be unity\&.
!> 
.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 REAL array, dimension at least
!>           ( 1 + ( n - 1 )*abs( INCX ) )\&.
!>           Before entry, the incremented array X must contain the n
!>           element vector x\&. On exit, X is overwritten with the
!>           transformed 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
 
.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 \fB185\fP of file \fBstbmv\&.f\fP\&.
.SH "Author"
.PP 
Generated automatically by Doxygen for LAPACK from the source code\&.