Rank-2 update

SSYR2/DSYR2/CHER2/ZHER2

Example 2

Apply a COMPLEX*8 Hermitian rank-2 update αx y*+

α

yx* to A, where A is a

 

9-by-9 complex Hermitian matrix whose lower triangle is stored in the lower

 

triangle of an array A whose dimensions are 10-by-10, α is a complex scalar, x is

 

a complex vector 9 elements long stored in an array X of dimension 10, and y is

 

a complex vector 9 elements long stored in an array Y of dimension 10.

 

INTEGER*4 N,LDA

 

COMPLEX*8 ALPHA,A(10,10),X(10),Y(10)

 

N = 9

 

LDA = 10

 

CALL CHER2 (’LOWER’,N,ALPHA,X,1,Y,1,A,LDA)

Chapter 3 Basic Matrix Operations 283