[uplo,n,alpha,x,incx,a,lda]=cher(uplo,n,alpha,x,incx,a,lda);

function [uplo,n,alpha,x,incx,a,lda]=cher(uplo,n,alpha,x,incx,a,lda);
%***BEGIN PROLOGUE  CHER
%***PURPOSE  Perform Hermitian rank 1 update of a complex Hermitian
%            matrix.
%***LIBRARY   SLATEC (BLAS)
%***CATEGORY  D1B4
%***TYPE      COMPLEX (SHER-S, DHER-D, CHER-C)
%***KEYWORDS  LEVEL 2 BLAS, LINEAR ALGEBRA
%***AUTHOR  Dongarra, J. J., (ANL)
%           Du Croz, J., (NAG)
%           Hammarling, S., (NAG)
%           Hanson, R. J., (SNLA)
%***DESCRIPTION
%
%  CHER   performs the hermitian rank 1 operation
%
%     A := alpha*x*conjg( x') + A,
%
%  where alpha is a real scalar, x is an n element vector and A is an
%  n by n hermitian matrix.
%
%  Parameters
%  ==========
%
%  UPLO   - 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.
%
%           Unchanged on exit.
%
%  N      - INTEGER.
%           On entry, N specifies the order of the matrix A.
%           N must be at least zero.
%           Unchanged on exit.
%
%  ALPHA  - REAL            .
%           On entry, ALPHA specifies the scalar alpha.
%           Unchanged on exit.
%
%  X      - COMPLEX          array of dimension at least
%           ( 1 + ( n - 1 )*abs( INCX ) ).
%           Before entry, the incremented array X must contain the n
%           element vector x.
%           Unchanged on exit.
%
%  INCX   - INTEGER.
%           On entry, INCX specifies the increment for the elements of
%           X. INCX must not be zero.
%           Unchanged on exit.
%
%  A      - COMPLEX          array of 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 hermitian 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 hermitian 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.
%           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.
%
%  LDA    - 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 ).
%           Unchanged on exit.
%
%***REFERENCES  Dongarra, J. J., Du Croz, J., Hammarling, S., and
%                 Hanson, R. J.  An extended set of Fortran basic linear
%                 algebra subprograms.  ACM TOMS, Vol. 14, No. 1,
%                 pp. 1-17, March 1988.
%***ROUTINES CALLED  LSAME, XERBLA
%***REVISION HISTORY  (YYMMDD)
%   861022  DATE WRITTEN
%   910605  Modified to meet SLATEC prologue standards.  Only comment
%           lines were modified.  (BKS)
%***end PROLOGUE  CHER
%     .. Scalar Arguments ..
%     .. Array Arguments ..
persistent i info ix j jx kx temp zero ; 

a_shape=size(a);a=reshape([a(:).',zeros(1,ceil(numel(a)./prod([lda])).*prod([lda])-numel(a))],lda,[]);
x_shape=size(x);x=reshape(x,1,[]);
%     .. Parameters ..
if isempty(zero), zero=complex(0.0e+0,0.0e+0) ; end;
%     .. Local Scalars ..
if isempty(temp), temp=0; end;
if isempty(i), i=0; end;
if isempty(info), info=0; end;
if isempty(ix), ix=0; end;
if isempty(j), j=0; end;
if isempty(jx), jx=0; end;
if isempty(kx), kx=0; end;
%     .. External Functions ..
%     .. External Subroutines ..
%     .. Intrinsic Functions ..
% intrinsic conjg , max , real ::;
%***FIRST EXECUTABLE STATEMENT  CHER
%
%     Test the input parameters.
%
info = 0;
if( ~lsame(uplo,'U') && ~lsame(uplo,'L') )
info = 1;
elseif( n<0 ) ;
info = 2;
elseif( incx==0 ) ;
info = 5;
elseif( lda<max(1,n) ) ;
info = 7;
end;
if( info~=0 )
[dumvar1,info]=xerbla('CHER  ',info);
a_shape=zeros(a_shape);a_shape(:)=a(1:numel(a_shape));a=a_shape;
x_shape=zeros(x_shape);x_shape(:)=x(1:numel(x_shape));x=x_shape;
return;
end;
%
%     Quick return if possible.
%
if((n==0) ||(alpha==real(zero)) )
a_shape=zeros(a_shape);a_shape(:)=a(1:numel(a_shape));a=a_shape;
x_shape=zeros(x_shape);x_shape(:)=x(1:numel(x_shape));x=x_shape;
return;
end;
%
%     Set the start point in X if the increment is not unity.
%
if( incx<=0 )
kx = fix(1 -(n-1).*incx);
elseif( incx~=1 ) ;
kx = 1;
end;
%
%     Start the operations. In this version the elements of A are
%     accessed sequentially with one pass through the triangular part
%     of A.
%
if( lsame(uplo,'U') )
%
%        Form  A  when A is stored in upper triangle.
%
if( incx==1 )
for j = 1 : n;
if( x(j)~=zero )
temp = alpha.*conj(x(j));
for i = 1 : j - 1;
a(i,j) = a(i,j) + x(i).*temp;
end; i = fix(j - 1+1);
a(j,j) = real(a(j,j)) + real(x(j).*temp);
else;
a(j,j) = real(a(j,j));
end;
end; j = fix(n+1);
else;
jx = fix(kx);
for j = 1 : n;
if( x(jx)~=zero )
temp = alpha.*conj(x(jx));
ix = fix(kx);
for i = 1 : j - 1;
a(i,j) = a(i,j) + x(ix).*temp;
ix = fix(ix + incx);
end; i = fix(j - 1+1);
a(j,j) = real(a(j,j)) + real(x(jx).*temp);
else;
a(j,j) = real(a(j,j));
end;
jx = fix(jx + incx);
end; j = fix(n+1);
end;
%
%        Form  A  when A is stored in lower triangle.
%
elseif( incx==1 ) ;
for j = 1 : n;
if( x(j)~=zero )
temp = alpha.*conj(x(j));
a(j,j) = real(a(j,j)) + real(temp.*x(j));
for i = j + 1 : n;
a(i,j) = a(i,j) + x(i).*temp;
end; i = fix(n+1);
else;
a(j,j) = real(a(j,j));
end;
end; j = fix(n+1);
else;
jx = fix(kx);
for j = 1 : n;
if( x(jx)~=zero )
temp = alpha.*conj(x(jx));
a(j,j) = real(a(j,j)) + real(temp.*x(jx));
ix = fix(jx);
for i = j + 1 : n;
ix = fix(ix + incx);
a(i,j) = a(i,j) + x(ix).*temp;
end; i = fix(n+1);
else;
a(j,j) = real(a(j,j));
end;
jx = fix(jx + incx);
end; j = fix(n+1);
end;
%
%
%     end of CHER  .
%
a_shape=zeros(a_shape);a_shape(:)=a(1:numel(a_shape));a=a_shape;
x_shape=zeros(x_shape);x_shape(:)=x(1:numel(x_shape));x=x_shape;
end
%DECK CHERK