LAPACK
3.4.2
LAPACK: Linear Algebra PACKage

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Functions/Subroutines  
subroutine  cspr (UPLO, N, ALPHA, X, INCX, AP) 
CSPR performs the symmetrical rank1 update of a complex symmetric packed matrix. 
subroutine cspr  (  character  UPLO, 
integer  N,  
complex  ALPHA,  
complex, dimension( * )  X,  
integer  INCX,  
complex, dimension( * )  AP  
) 
CSPR performs the symmetrical rank1 update of a complex symmetric packed matrix.
Download CSPR + dependencies [TGZ] [ZIP] [TXT]CSPR performs the symmetric rank 1 operation A := alpha*x*x**H + A, where alpha is a complex scalar, x is an n element vector and A is an n by n symmetric matrix, supplied in packed form.
[in]  UPLO  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. Unchanged on exit. 
[in]  N  N is INTEGER On entry, N specifies the order of the matrix A. N must be at least zero. Unchanged on exit. 
[in]  ALPHA  ALPHA is COMPLEX On entry, ALPHA specifies the scalar alpha. Unchanged on exit. 
[in]  X  X is COMPLEX array, dimension at least ( 1 + ( N  1 )*abs( INCX ) ). Before entry, the incremented array X must contain the N element vector x. Unchanged on exit. 
[in]  INCX  INCX is INTEGER On entry, INCX specifies the increment for the elements of X. INCX must not be zero. Unchanged on exit. 
[in,out]  AP  AP is COMPLEX 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. On exit, the array AP is overwritten by the upper triangular part of the updated matrix. 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. On exit, the array AP is overwritten by the lower triangular part of the updated matrix. Note that the imaginary parts of the diagonal elements need not be set, they are assumed to be zero, and on exit they are set to zero. 
Definition at line 133 of file cspr.f.