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

.in +1c
.ti -1c
.RI "subroutine \fBsspmv\fP (uplo, n, alpha, ap, x, incx, beta, y, incy)"
.br
.RI "\fBSSPMV\fP "
.in -1c
.SH "Function/Subroutine Documentation"
.PP 
.SS "subroutine sspmv (character uplo, integer n, real alpha, real, dimension(*) ap, real, dimension(*) x, integer incx, real beta, real, dimension(*) y, integer incy)"

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

.PP
.nf
!>
!> SSPMV  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 symmetric matrix, supplied in packed form\&.
!> 
.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 matrix A is supplied in the packed
!>           array AP as follows:
!>
!>              UPLO = 'U' or 'u'   The upper triangular part of A is
!>                                  supplied in AP\&.
!>
!>              UPLO = 'L' or 'l'   The lower triangular part of A is
!>                                  supplied in AP\&.
!> 
.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
\fIALPHA\fP 
.PP
.nf
!>          ALPHA is REAL
!>           On entry, ALPHA specifies the scalar alpha\&.
!> 
.fi
.PP
.br
\fIAP\fP 
.PP
.nf
!>          AP is REAL array, dimension at least
!>           ( ( n*( n + 1 ) )/2 )\&.
!>           Before entry with UPLO = 'U' or 'u', the array AP must
!>           contain the upper triangular part of the symmetric matrix
!>           packed sequentially, column by column, so that AP( 1 )
!>           contains a( 1, 1 ), AP( 2 ) and AP( 3 ) contain a( 1, 2 )
!>           and a( 2, 2 ) respectively, and so on\&.
!>           Before entry with UPLO = 'L' or 'l', the array AP must
!>           contain the lower triangular part of the symmetric matrix
!>           packed sequentially, column by column, so that AP( 1 )
!>           contains a( 1, 1 ), AP( 2 ) and AP( 3 ) contain a( 2, 1 )
!>           and a( 3, 1 ) respectively, and so on\&.
!> 
.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\&.
!> 
.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 REAL
!>           On entry, BETA specifies the scalar beta\&. When BETA is
!>           supplied as zero then Y need not be set on input\&.
!> 
.fi
.PP
.br
\fIY\fP 
.PP
.nf
!>          Y is REAL array, dimension at least
!>           ( 1 + ( n - 1 )*abs( INCY ) )\&.
!>           Before entry, the incremented array Y must contain the n
!>           element 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 \fB146\fP of file \fBsspmv\&.f\fP\&.
.SH "Author"
.PP 
Generated automatically by Doxygen for LAPACK from the source code\&.