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program example_solve3
use stdlib_linalg_constants, only: sp,ilp
use stdlib_linalg, only: solve_lu, linalg_state_type
implicit none
integer(ilp) :: test
integer(ilp), allocatable :: pivot(:)
complex(sp), allocatable :: A(:,:),b(:),x(:)
! Solve a system of 3 complex linear equations:
! 2x + iy + 2z = (5-i)
! -ix + (4-3i)y + 6z = i
! 4x + 3y + z = 1
! Note: Fortran is column-major! -> transpose
A = transpose(reshape([(2.0, 0.0),(0.0, 1.0),(2.0,0.0), &
(0.0,-1.0),(4.0,-3.0),(6.0,0.0), &
(4.0, 0.0),(3.0, 0.0),(1.0,0.0)] , [3,3]))
! Pre-allocate x
allocate(b(size(A,2)),pivot(size(A,2)))
allocate(x,mold=b)
! Call system many times avoiding reallocation
do test=1,100
b = test*[(5.0,-1.0),(0.0,1.0),(1.0,0.0)]
call solve_lu(A,b,x,pivot)
print "(i3,'-th solution: ',*(1x,f12.6))", test,x
end do
end program example_solve3
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