.TH "BLAS/SRC/ssyr2.f" 3 "Version 3.12.0" "LAPACK" \" -*- nroff -*- .ad l .nh .SH NAME BLAS/SRC/ssyr2.f .SH SYNOPSIS .br .PP .SS "Functions/Subroutines" .in +1c .ti -1c .RI "subroutine \fBssyr2\fP (uplo, n, alpha, x, incx, y, incy, a, lda)" .br .RI "\fBSSYR2\fP " .in -1c .SH "Function/Subroutine Documentation" .PP .SS "subroutine ssyr2 (character uplo, integer n, real alpha, real, dimension(*) x, integer incx, real, dimension(*) y, integer incy, real, dimension(lda,*) a, integer lda)" .PP \fBSSYR2\fP .PP \fBPurpose:\fP .RS 4 .PP .nf !> !> SSYR2 performs the symmetric rank 2 operation !> !> A := alpha*x*y**T + alpha*y*x**T + A, !> !> where alpha is a scalar, x and y are n element vectors and A is an n !> by n symmetric matrix\&. !> .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 array A is to be referenced as !> follows: !> !> UPLO = 'U' or 'u' Only the upper triangular part of A !> is to be referenced\&. !> !> UPLO = 'L' or 'l' Only the lower triangular part of A !> is to be referenced\&. !> .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 \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 \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\&. !> .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 .br \fIA\fP .PP .nf !> A is REAL array, dimension ( LDA, N ) !> Before entry with UPLO = 'U' or 'u', the leading n by n !> upper triangular part of the array A must contain the upper !> triangular part of the symmetric matrix and the strictly !> lower triangular part of A is not referenced\&. On exit, the !> upper triangular part of the array A is overwritten by the !> upper triangular part of the updated matrix\&. !> Before entry with UPLO = 'L' or 'l', the leading n by n !> lower triangular part of the array A must contain the lower !> triangular part of the symmetric matrix and the strictly !> upper triangular part of A is not referenced\&. On exit, the !> lower triangular part of the array A is overwritten by the !> lower triangular part of the updated matrix\&. !> .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 !> max( 1, n )\&. !> .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\&. !> !> -- 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 \fBssyr2\&.f\fP\&. .SH "Author" .PP Generated automatically by Doxygen for LAPACK from the source code\&.