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program least_square
include 'link_fnl_shared.h'
use imsl_libraries
integer, parameter :: m = 5
integer, parameter :: n = 2
integer :: i
double precision :: A(m,n), B(m), X(n)
double precision :: C(n, m), D(n,n), E(n)
data A / 2, 8, 2, 7, 4, -1, 4, 1, -1, 0 /
data B / 1, 0, 1, 8, 3 /
if( m > n ) then
C = transpose(a)
D = matmul( c, a )
E = matmul( c, b )
X = D .ix. E ! invert(D) * E
else if( m == n ) then
X = A .ix. B
else
write(*,*) "No roots!"
end if
do i = 1, n
write(*,*) X(i)
end do
stop
end program least_square