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32 lines
835 B
Fortran
32 lines
835 B
Fortran
subroutine extrapolate_data(N_data, data, pt2, output)
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implicit none
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BEGIN_DOC
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! Extrapolate the data to the FCI limit
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END_DOC
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integer, intent(in) :: N_data
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double precision, intent(in) :: data(N_data)
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double precision, intent(in) :: pt2(N_data)
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double precision, intent(out) :: output(N_data)
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double precision :: data_rev(N_data), pt2_rev(N_data)
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integer :: ifit, i,j
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double precision :: ab(2), x(N_data,2), x_inv(2,N_data), y(N_data)
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do i=1,N_data
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data_rev(N_data+1-i) = data(i)
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pt2_rev(N_data+1-i) = pt2(i)
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enddo
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do i=1,N_data
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y(i) = data_rev(i)
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x(i,1) = 1.d0
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x(i,2) = pt2_rev(i)
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enddo
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do ifit=2,N_data
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call get_pseudo_inverse(x,size(x,1),ifit,2,x_inv,size(x_inv,1),1.d-10)
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ab = matmul(x_inv(1:2,1:ifit),y(1:ifit))
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output(ifit) = ab(1)
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enddo
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end
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