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qp2/src/utils/integration.irp.f

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2019-01-25 11:39:31 +01:00
subroutine give_explicit_poly_and_gaussian_x(P_new,P_center,p,fact_k,iorder,alpha,beta,a,b,A_center,B_center,dim)
BEGIN_DOC
! Transform the product of
! (x-x_A)^a(1) (x-x_B)^b(1) (x-x_A)^a(2) (y-y_B)^b(2) (z-z_A)^a(3) (z-z_B)^b(3) exp(-(r-A)^2 alpha) exp(-(r-B)^2 beta)
! into
! fact_k (x-x_P)^iorder(1) (y-y_P)^iorder(2) (z-z_P)^iorder(3) exp(-p(r-P)^2)
END_DOC
implicit none
include 'constants.include.F'
integer, intent(in) :: dim
integer, intent(in) :: a,b ! powers : (x-xa)**a_x = (x-A(1))**a(1)
double precision, intent(in) :: alpha, beta ! exponents
double precision, intent(in) :: A_center ! A center
double precision, intent(in) :: B_center ! B center
double precision, intent(out) :: P_center ! new center
double precision, intent(out) :: p ! new exponent
double precision, intent(out) :: fact_k ! constant factor
double precision, intent(out) :: P_new(0:max_dim) ! polynomial
integer, intent(out) :: iorder ! order of the polynomials
double precision :: P_a(0:max_dim), P_b(0:max_dim)
integer :: n_new,i,j
double precision :: p_inv,ab,d_AB
!DIR$ ATTRIBUTES ALIGN : $IRP_ALIGN :: P_a, P_b
! Do the gaussian product to get the new center and the new exponent
P_new = 0.d0
p = alpha+beta
p_inv = 1.d0/p
ab = alpha * beta
d_AB = (A_center - B_center) * (A_center - B_center)
P_center = (alpha * A_center + beta * B_center) * p_inv
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if(dabs(ab*p_inv * d_AB).lt.50.d0)then
fact_k = exp(-ab*p_inv * d_AB)
else
fact_k = 0.d0
endif
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! Recenter the polynomials P_a and P_b on x
!DIR$ FORCEINLINE
call recentered_poly2(P_a(0),A_center,P_center,a,P_b(0),B_center,P_center,b)
n_new = 0
!DIR$ FORCEINLINE
call multiply_poly(P_a(0),a,P_b(0),b,P_new(0),n_new)
iorder = a + b
end
subroutine give_explicit_poly_and_gaussian(P_new,P_center,p,fact_k,iorder,alpha,beta,a,b,A_center,B_center,dim)
BEGIN_DOC
! Transforms the product of
! (x-x_A)^a(1) (x-x_B)^b(1) (x-x_A)^a(2) (y-y_B)^b(2) (z-z_A)^a(3) (z-z_B)^b(3) exp(-(r-A)^2 alpha) exp(-(r-B)^2 beta)
! into
! fact_k * [ sum (l_x = 0,i_order(1)) P_new(l_x,1) * (x-P_center(1))^l_x ] exp (- p (x-P_center(1))^2 )
! * [ sum (l_y = 0,i_order(2)) P_new(l_y,2) * (y-P_center(2))^l_y ] exp (- p (y-P_center(2))^2 )
! * [ sum (l_z = 0,i_order(3)) P_new(l_z,3) * (z-P_center(3))^l_z ] exp (- p (z-P_center(3))^2 )
!
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! WARNING ::: IF fact_k is too smal then:
! returns a "s" function centered in zero
! with an inifinite exponent and a zero polynom coef
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END_DOC
implicit none
include 'constants.include.F'
integer, intent(in) :: dim
integer, intent(in) :: a(3),b(3) ! powers : (x-xa)**a_x = (x-A(1))**a(1)
double precision, intent(in) :: alpha, beta ! exponents
double precision, intent(in) :: A_center(3) ! A center
double precision, intent(in) :: B_center (3) ! B center
double precision, intent(out) :: P_center(3) ! new center
double precision, intent(out) :: p ! new exponent
double precision, intent(out) :: fact_k ! constant factor
double precision, intent(out) :: P_new(0:max_dim,3)! polynomial
integer, intent(out) :: iorder(3) ! i_order(i) = order of the polynomials
double precision :: P_a(0:max_dim,3), P_b(0:max_dim,3)
integer :: n_new,i,j
!DIR$ ATTRIBUTES ALIGN : $IRP_ALIGN :: P_a, P_b
iorder(1) = 0
iorder(2) = 0
iorder(3) = 0
P_new(0,1) = 0.d0
P_new(0,2) = 0.d0
P_new(0,3) = 0.d0
!DIR$ FORCEINLINE
call gaussian_product(alpha,A_center,beta,B_center,fact_k,p,P_center)
if (fact_k < thresh) then
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! IF fact_k is too smal then:
! returns a "s" function centered in zero
! with an inifinite exponent and a zero polynom coef
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P_center = 0.d0
p = 1.d+15
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P_new = 0.d0
iorder = 0
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fact_k = 0.d0
return
endif
!DIR$ FORCEINLINE
call recentered_poly2(P_a(0,1),A_center(1),P_center(1),a(1),P_b(0,1),B_center(1),P_center(1),b(1))
iorder(1) = a(1) + b(1)
do i=0,iorder(1)
P_new(i,1) = 0.d0
enddo
n_new=0
!DIR$ FORCEINLINE
call multiply_poly(P_a(0,1),a(1),P_b(0,1),b(1),P_new(0,1),n_new)
!DIR$ FORCEINLINE
call recentered_poly2(P_a(0,2),A_center(2),P_center(2),a(2),P_b(0,2),B_center(2),P_center(2),b(2))
iorder(2) = a(2) + b(2)
do i=0,iorder(2)
P_new(i,2) = 0.d0
enddo
n_new=0
!DIR$ FORCEINLINE
call multiply_poly(P_a(0,2),a(2),P_b(0,2),b(2),P_new(0,2),n_new)
!DIR$ FORCEINLINE
call recentered_poly2(P_a(0,3),A_center(3),P_center(3),a(3),P_b(0,3),B_center(3),P_center(3),b(3))
iorder(3) = a(3) + b(3)
do i=0,iorder(3)
P_new(i,3) = 0.d0
enddo
n_new=0
!DIR$ FORCEINLINE
call multiply_poly(P_a(0,3),a(3),P_b(0,3),b(3),P_new(0,3),n_new)
end
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subroutine give_explicit_poly_and_gaussian_v(P_new, ldp, P_center, p, fact_k, iorder, alpha, beta, a, b, A_center, LD_A, B_center, n_points)
BEGIN_DOC
! Transforms the product of
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! (x-x_A)^a(1) (x-x_B)^b(1) (y-y_A)^a(2) (y-y_B)^b(2) (z-z_A)^a(3) (z-z_B)^b(3) exp(-(r-A)^2 alpha) exp(-(r-B)^2 beta)
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! into
! fact_k * [ sum (l_x = 0,i_order(1)) P_new(l_x,1) * (x-P_center(1))^l_x ] exp (- p (x-P_center(1))^2 )
! * [ sum (l_y = 0,i_order(2)) P_new(l_y,2) * (y-P_center(2))^l_y ] exp (- p (y-P_center(2))^2 )
! * [ sum (l_z = 0,i_order(3)) P_new(l_z,3) * (z-P_center(3))^l_z ] exp (- p (z-P_center(3))^2 )
!
! WARNING :: : IF fact_k is too smal then:
! returns a "s" function centered in zero
! with an inifinite exponent and a zero polynom coef
END_DOC
include 'constants.include.F'
implicit none
integer, intent(in) :: n_points, ldp, LD_A
integer, intent(in) :: a(3), b(3) ! powers : (x-xa)**a_x = (x-A(1))**a(1)
double precision, intent(in) :: alpha, beta ! exponents
double precision, intent(in) :: A_center(LD_A,3) ! A center
double precision, intent(in) :: B_center(3) ! B center
integer, intent(out) :: iorder(3) ! i_order(i) = order of the polynomials
double precision, intent(out) :: P_center(n_points,3) ! new center
double precision, intent(out) :: p ! new exponent
double precision, intent(out) :: fact_k(n_points) ! constant factor
double precision, intent(out) :: P_new(n_points,0:ldp,3) ! polynomial
integer :: n_new, i, j, ipoint, lda, ldb, xyz
double precision, allocatable :: P_a(:,:,:), P_b(:,:,:)
call gaussian_product_v(alpha, A_center, LD_A, beta, B_center, fact_k, p, P_center, n_points)
if(ior(ior(b(1), b(2)), b(3)) == 0) then ! b == (0,0,0)
iorder(1:3) = a(1:3)
lda = maxval(a)
allocate(P_a(n_points,0:lda,3))
!ldb = 0
!allocate(P_b(n_points,0:0,3))
!call recentered_poly2_v0(P_a, lda, A_center, LD_A, P_center, a, P_b, B_center, P_center, n_points)
call recentered_poly2_v0(P_a, lda, A_center, LD_A, P_center, a, n_points)
do ipoint = 1, n_points
do xyz = 1, 3
!P_new(ipoint,0,xyz) = P_a(ipoint,0,xyz) * P_b(ipoint,0,xyz)
P_new(ipoint,0,xyz) = P_a(ipoint,0,xyz)
do i = 1, a(xyz)
!P_new(ipoint,i,xyz) = P_new(ipoint,i,xyz) + P_b(ipoint,0,xyz) * P_a(ipoint,i,xyz)
P_new(ipoint,i,xyz) = P_a(ipoint,i,xyz)
enddo
enddo
enddo
deallocate(P_a)
!deallocate(P_b)
return
endif
lda = maxval(a)
ldb = maxval(b)
allocate(P_a(n_points,0:lda,3), P_b(n_points,0:ldb,3))
call recentered_poly2_v(P_a, lda, A_center, LD_A, P_center, a, P_b, ldb, B_center, P_center, b, n_points)
iorder(1:3) = a(1:3) + b(1:3)
do xyz = 1, 3
if(b(xyz) == 0) then
do ipoint = 1, n_points
!P_new(ipoint,0,xyz) = P_a(ipoint,0,xyz) * P_b(ipoint,0,xyz)
P_new(ipoint,0,xyz) = P_a(ipoint,0,xyz)
do i = 1, a(xyz)
!P_new(ipoint,i,xyz) = P_new(ipoint,i,xyz) + P_b(ipoint,0,xyz) * P_a(ipoint,i,xyz)
P_new(ipoint,i,xyz) = P_a(ipoint,i,xyz)
enddo
enddo
else
do i = 0, iorder(xyz)
do ipoint = 1, n_points
P_new(ipoint,i,xyz) = 0.d0
enddo
enddo
call multiply_poly_v(P_a(1,0,xyz), a(xyz), P_b(1,0,xyz), b(xyz), P_new(1,0,xyz), ldp, n_points)
endif
enddo
end subroutine give_explicit_poly_and_gaussian_v
! ---
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subroutine give_explicit_poly_and_gaussian_double(P_new,P_center,p,fact_k,iorder,alpha,beta,gama,a,b,A_center,B_center,Nucl_center,dim)
BEGIN_DOC
! Transforms the product of
! (x-x_A)^a(1) (x-x_B)^b(1) (x-x_A)^a(2) (y-y_B)^b(2) (z-z_A)^a(3) (z-z_B)^b(3)
! exp(-(r-A)^2 alpha) exp(-(r-B)^2 beta) exp(-(r-Nucl_center)^2 gama
!
! into
! fact_k * [ sum (l_x = 0,i_order(1)) P_new(l_x,1) * (x-P_center(1))^l_x ] exp (- p (x-P_center(1))^2 )
! * [ sum (l_y = 0,i_order(2)) P_new(l_y,2) * (y-P_center(2))^l_y ] exp (- p (y-P_center(2))^2 )
! * [ sum (l_z = 0,i_order(3)) P_new(l_z,3) * (z-P_center(3))^l_z ] exp (- p (z-P_center(3))^2 )
END_DOC
implicit none
include 'constants.include.F'
integer, intent(in) :: dim
integer, intent(in) :: a(3),b(3) ! powers : (x-xa)**a_x = (x-A(1))**a(1)
double precision, intent(in) :: alpha, beta, gama ! exponents
double precision, intent(in) :: A_center(3) ! A center
double precision, intent(in) :: B_center (3) ! B center
double precision, intent(in) :: Nucl_center(3) ! B center
double precision, intent(out) :: P_center(3) ! new center
double precision, intent(out) :: p ! new exponent
double precision, intent(out) :: fact_k ! constant factor
double precision, intent(out) :: P_new(0:max_dim,3)! polynomial
integer , intent(out) :: iorder(3) ! i_order(i) = order of the polynomials
double precision :: P_center_tmp(3) ! new center
double precision :: p_tmp ! new exponent
double precision :: fact_k_tmp,fact_k_bis ! constant factor
double precision :: P_new_tmp(0:max_dim,3)! polynomial
integer :: i,j
double precision :: binom_func
! First you transform the two primitives into a sum of primitive with the same center P_center_tmp and gaussian exponent p_tmp
call give_explicit_poly_and_gaussian(P_new_tmp,P_center_tmp,p_tmp,fact_k_tmp,iorder,alpha,beta,a,b,A_center,B_center,dim)
! Then you create the new gaussian from the product of the new one per the Nuclei one
call gaussian_product(p_tmp,P_center_tmp,gama,Nucl_center,fact_k_bis,p,P_center)
fact_k = fact_k_bis * fact_k_tmp
! Then you build the coefficient of the new polynom
do i = 0, iorder(1)
P_new(i,1) = 0.d0
do j = i,iorder(1)
P_new(i,1) = P_new(i,1) + P_new_tmp(j,1) * binom_func(j,j-i) * (P_center(1) - P_center_tmp(1))**(j-i)
enddo
enddo
do i = 0, iorder(2)
P_new(i,2) = 0.d0
do j = i,iorder(2)
P_new(i,2) = P_new(i,2) + P_new_tmp(j,2) * binom_func(j,j-i) * (P_center(2) - P_center_tmp(2))**(j-i)
enddo
enddo
do i = 0, iorder(3)
P_new(i,3) = 0.d0
do j = i,iorder(3)
P_new(i,3) = P_new(i,3) + P_new_tmp(j,3) * binom_func(j,j-i) * (P_center(3) - P_center_tmp(3))**(j-i)
enddo
enddo
end
subroutine gaussian_product(a,xa,b,xb,k,p,xp)
implicit none
BEGIN_DOC
! Gaussian product in 1D.
! e^{-a (x-x_A)^2} e^{-b (x-x_B)^2} = K_{ab}^x e^{-p (x-x_P)^2}
END_DOC
double precision, intent(in) :: a,b ! Exponents
double precision, intent(in) :: xa(3),xb(3) ! Centers
double precision, intent(out) :: p ! New exponent
double precision, intent(out) :: xp(3) ! New center
double precision, intent(out) :: k ! Constant
double precision :: p_inv
ASSERT (a>0.)
ASSERT (b>0.)
double precision :: xab(3), ab
!DIR$ ATTRIBUTES ALIGN : $IRP_ALIGN :: xab
p = a+b
p_inv = 1.d0/(a+b)
ab = a*b
xab(1) = xa(1)-xb(1)
xab(2) = xa(2)-xb(2)
xab(3) = xa(3)-xb(3)
ab = ab*p_inv
k = ab*(xab(1)*xab(1)+xab(2)*xab(2)+xab(3)*xab(3))
if (k > 40.d0) then
k=0.d0
return
endif
k = dexp(-k)
xp(1) = (a*xa(1)+b*xb(1))*p_inv
xp(2) = (a*xa(2)+b*xb(2))*p_inv
xp(3) = (a*xa(3)+b*xb(3))*p_inv
end subroutine
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subroutine gaussian_product_v(a, xa, LD_xa, b, xb, k, p, xp, n_points)
BEGIN_DOC
!
! Gaussian product in 1D.
! e^{-a (x-x_A)^2} e^{-b (x-x_B)^2} = K_{ab}^x e^{-p (x-x_P)^2}
!
! Using multiple A centers
!
END_DOC
implicit none
integer, intent(in) :: LD_xa, n_points
double precision, intent(in) :: a, b ! Exponents
double precision, intent(in) :: xa(LD_xa,3), xb(3) ! Centers
double precision, intent(out) :: p ! New exponent
double precision, intent(out) :: xp(n_points,3) ! New center
double precision, intent(out) :: k(n_points) ! Constant
integer :: ipoint
double precision :: p_inv
double precision :: xab(3), ab, ap, bp, bpxb(3)
!DIR$ ATTRIBUTES ALIGN : $IRP_ALIGN :: xab
ASSERT (a>0.)
ASSERT (b>0.)
p = a+b
p_inv = 1.d0/(a+b)
ab = a*b*p_inv
ap = a*p_inv
bp = b*p_inv
bpxb(1) = bp*xb(1)
bpxb(2) = bp*xb(2)
bpxb(3) = bp*xb(3)
do ipoint = 1, n_points
xab(1) = xa(ipoint,1)-xb(1)
xab(2) = xa(ipoint,2)-xb(2)
xab(3) = xa(ipoint,3)-xb(3)
k(ipoint) = ab*(xab(1)*xab(1)+xab(2)*xab(2)+xab(3)*xab(3))
if (k(ipoint) > 40.d0) then
k(ipoint)=0.d0
xp(ipoint,1) = 0.d0
xp(ipoint,2) = 0.d0
xp(ipoint,3) = 0.d0
else
k(ipoint) = dexp(-k(ipoint))
xp(ipoint,1) = ap*xa(ipoint,1)+bpxb(1)
xp(ipoint,2) = ap*xa(ipoint,2)+bpxb(2)
xp(ipoint,3) = ap*xa(ipoint,3)+bpxb(3)
endif
enddo
end subroutine gaussian_product_v
! ---
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subroutine gaussian_product_x(a,xa,b,xb,k,p,xp)
implicit none
BEGIN_DOC
! Gaussian product in 1D.
! e^{-a (x-x_A)^2} e^{-b (x-x_B)^2} = K_{ab}^x e^{-p (x-x_P)^2}
END_DOC
double precision , intent(in) :: a,b ! Exponents
double precision , intent(in) :: xa,xb ! Centers
double precision , intent(out) :: p ! New exponent
double precision , intent(out) :: xp ! New center
double precision , intent(out) :: k ! Constant
double precision :: p_inv
ASSERT (a>0.)
ASSERT (b>0.)
double precision :: xab, ab
p = a+b
p_inv = 1.d0/(a+b)
ab = a*b
xab = xa-xb
ab = ab*p_inv
k = ab*xab*xab
if (k > 400.d0) then
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k=0.d0
return
endif
k = exp(-k)
xp = (a*xa+b*xb)*p_inv
end subroutine
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!-
subroutine gaussian_product_x_v(a,xa,b,xb,k,p,xp,n_points)
implicit none
BEGIN_DOC
! Gaussian product in 1D with multiple xa
! e^{-a (x-x_A)^2} e^{-b (x-x_B)^2} = K_{ab}^x e^{-p (x-x_P)^2}
END_DOC
integer, intent(in) :: n_points
double precision , intent(in) :: a,b ! Exponents
double precision , intent(in) :: xa(n_points),xb ! Centers
double precision , intent(out) :: p(n_points) ! New exponent
double precision , intent(out) :: xp(n_points) ! New center
double precision , intent(out) :: k(n_points) ! Constant
double precision :: p_inv
integer :: ipoint
ASSERT (a>0.)
ASSERT (b>0.)
double precision :: xab, ab
p = a+b
p_inv = 1.d0/(a+b)
ab = a*b*p_inv
do ipoint = 1, n_points
xab = xa(ipoint)-xb
k(ipoint) = ab*xab*xab
if (k(ipoint) > 40.d0) then
k(ipoint)=0.d0
cycle
endif
k(ipoint) = exp(-k(ipoint))
xp(ipoint) = (a*xa(ipoint)+b*xb)*p_inv
enddo
end subroutine
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subroutine multiply_poly(b,nb,c,nc,d,nd)
implicit none
BEGIN_DOC
! Multiply two polynomials
! D(t) += B(t)*C(t)
END_DOC
integer, intent(in) :: nb, nc
integer, intent(out) :: nd
double precision, intent(in) :: b(0:nb), c(0:nc)
double precision, intent(inout) :: d(0:nb+nc)
integer :: ndtmp
integer :: ib, ic, id, k
if(ior(nc,nb) < 0) return !False if nc>=0 and nb>=0
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select case (nb)
case (0)
call multiply_poly_b0(b,c,nc,d,nd)
return
case (1)
call multiply_poly_b1(b,c,nc,d,nd)
return
case (2)
call multiply_poly_b2(b,c,nc,d,nd)
return
end select
select case (nc)
case (0)
call multiply_poly_c0(b,nb,c,d,nd)
return
case (1)
call multiply_poly_c1(b,nb,c,d,nd)
return
case (2)
call multiply_poly_c2(b,nb,c,d,nd)
return
end select
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do ib=0,nb
do ic = 0,nc
d(ib+ic) = d(ib+ic) + c(ic) * b(ib)
enddo
enddo
do nd = nb+nc,0,-1
if (d(nd) /= 0.d0) exit
enddo
end
subroutine multiply_poly_b0(b,c,nc,d,nd)
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implicit none
BEGIN_DOC
! Multiply two polynomials
! D(t) += B(t)*C(t)
END_DOC
integer, intent(in) :: nc
integer, intent(out) :: nd
double precision, intent(in) :: b(0:0), c(0:nc)
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double precision, intent(inout) :: d(0:nc)
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integer :: ndtmp
integer :: ic, id, k
if(nc < 0) return !False if nc>=0
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do ic = 0,nc
d(ic) = d(ic) + c(ic) * b(0)
enddo
do nd = nc,0,-1
if (d(nd) /= 0.d0) exit
enddo
end
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subroutine multiply_poly_b1(b,c,nc,d,nd)
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implicit none
BEGIN_DOC
! Multiply two polynomials
! D(t) += B(t)*C(t)
END_DOC
integer, intent(in) :: nc
integer, intent(out) :: nd
double precision, intent(in) :: b(0:1), c(0:nc)
double precision, intent(inout) :: d(0:1+nc)
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integer :: ndtmp
integer :: ib, ic, id, k
if(nc < 0) return !False if nc>=0
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select case (nc)
case (0)
d(0) = d(0) + c(0) * b(0)
d(1) = d(1) + c(0) * b(1)
case (1)
d(0) = d(0) + c(0) * b(0)
d(1) = d(1) + c(0) * b(1) + c(1) * b(0)
d(2) = d(2) + c(1) * b(1)
case default
d(0) = d(0) + c(0) * b(0)
do ic = 1,nc
d(ic) = d(ic) + c(ic) * b(0) + c(ic-1) * b(1)
enddo
d(nc+1) = d(nc+1) + c(nc) * b(1)
end select
do nd = 1+nc,0,-1
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if (d(nd) /= 0.d0) exit
enddo
end
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subroutine multiply_poly_b2(b,c,nc,d,nd)
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implicit none
BEGIN_DOC
! Multiply two polynomials
! D(t) += B(t)*C(t)
END_DOC
integer, intent(in) :: nc
integer, intent(out) :: nd
double precision, intent(in) :: b(0:2), c(0:nc)
double precision, intent(inout) :: d(0:2+nc)
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integer :: ndtmp
integer :: ib, ic, id, k
if(nc < 0) return !False if nc>=0
select case (nc)
case (0)
d(0) = d(0) + c(0) * b(0)
d(1) = d(1) + c(0) * b(1)
d(2) = d(2) + c(0) * b(2)
case (1)
d(0) = d(0) + c(0) * b(0)
d(1) = d(1) + c(0) * b(1) + c(1) * b(0)
d(2) = d(2) + c(0) * b(2) + c(1) * b(1)
d(3) = d(3) + c(1) * b(2)
case (2)
d(0) = d(0) + c(0) * b(0)
d(1) = d(1) + c(0) * b(1) + c(1) * b(0)
d(2) = d(2) + c(0) * b(2) + c(1) * b(1) + c(2) * b(0)
d(3) = d(3) + c(2) * b(1) + c(1) * b(2)
d(4) = d(4) + c(2) * b(2)
case default
d(0) = d(0) + c(0) * b(0)
d(1) = d(1) + c(0) * b(1) + c(1) * b(0)
do ic = 2,nc
d(ic) = d(ic) + c(ic) * b(0) + c(ic-1) * b(1) + c(ic-2) * b(2)
enddo
d(nc+1) = d(nc+1) + c(nc) * b(1) + c(nc-1) * b(2)
d(nc+2) = d(nc+2) + c(nc) * b(2)
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end select
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do nd = 2+nc,0,-1
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if (d(nd) /= 0.d0) exit
enddo
end
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subroutine multiply_poly_c0(b,nb,c,d,nd)
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implicit none
BEGIN_DOC
! Multiply two polynomials
! D(t) += B(t)*C(t)
END_DOC
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integer, intent(in) :: nb
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integer, intent(out) :: nd
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double precision, intent(in) :: b(0:nb), c(0:0)
double precision, intent(inout) :: d(0:nb)
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integer :: ndtmp
integer :: ib, ic, id, k
if(nb < 0) return !False if nb>=0
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do ib=0,nb
d(ib) = d(ib) + c(0) * b(ib)
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enddo
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do nd = nb,0,-1
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if (d(nd) /= 0.d0) exit
enddo
end
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subroutine multiply_poly_c1(b,nb,c,d,nd)
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implicit none
BEGIN_DOC
! Multiply two polynomials
! D(t) += B(t)*C(t)
END_DOC
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integer, intent(in) :: nb
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integer, intent(out) :: nd
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double precision, intent(in) :: b(0:nb), c(0:1)
double precision, intent(inout) :: d(0:nb+1)
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integer :: ndtmp
integer :: ib, ic, id, k
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if(nb < 0) return !False if nb>=0
select case (nb)
case (0)
d(0) = d(0) + c(0) * b(0)
d(1) = d(1) + c(1) * b(0)
case (1)
d(0) = d(0) + c(0) * b(0)
d(1) = d(1) + c(0) * b(1) + c(1) * b(0)
d(2) = d(2) + c(1) * b(1)
case default
d(0) = d(0) + c(0) * b(0)
do ib=1,nb
d(ib) = d(ib) + c(0) * b(ib) + c(1) * b(ib-1)
enddo
d(nb+1) = d(nb+1) + c(1) * b(nb)
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end select
do nd = nb+1,0,-1
if (d(nd) /= 0.d0) exit
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enddo
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end
subroutine multiply_poly_c2(b,nb,c,d,nd)
implicit none
BEGIN_DOC
! Multiply two polynomials
! D(t) += B(t)*C(t)
END_DOC
integer, intent(in) :: nb
integer, intent(out) :: nd
double precision, intent(in) :: b(0:nb), c(0:2)
double precision, intent(inout) :: d(0:nb+2)
integer :: ndtmp
integer :: ib, ic, id, k
if(nb < 0) return !False if nb>=0
select case (nb)
case (0)
d(0) = d(0) + c(0) * b(0)
d(1) = d(1) + c(1) * b(0)
d(2) = d(2) + c(2) * b(0)
case (1)
d(0) = d(0) + c(0) * b(0)
d(1) = d(1) + c(0) * b(1) + c(1) * b(0)
d(2) = d(2) + c(1) * b(1) + c(2) * b(0)
d(3) = d(3) + c(2) * b(1)
case (2)
d(0) = d(0) + c(0) * b(0)
d(1) = d(1) + c(0) * b(1) + c(1) * b(0)
d(2) = d(2) + c(0) * b(2) + c(1) * b(1) + c(2) * b(0)
d(3) = d(3) + c(1) * b(2) + c(2) * b(1)
d(4) = d(4) + c(2) * b(2)
case default
d(0) = d(0) + c(0) * b(0)
d(1) = d(1) + c(0) * b(1) + c(1) * b(0)
do ib=2,nb
d(ib) = d(ib) + c(0) * b(ib) + c(1) * b(ib-1) + c(2) * b(ib-2)
enddo
d(nb+1) = d(nb+1) + c(1) * b(nb) + c(2) * b(nb-1)
d(nb+2) = d(nb+2) + c(2) * b(nb)
end select
do nd = nb+2,0,-1
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if (d(nd) /= 0.d0) exit
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enddo
end
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subroutine multiply_poly_v(b,nb,c,nc,d,nd,n_points)
implicit none
BEGIN_DOC
! Multiply pairs of polynomials
! D(t) += B(t)*C(t)
END_DOC
integer, intent(in) :: nb, nc, n_points
integer, intent(in) :: nd
double precision, intent(in) :: b(n_points,0:nb), c(n_points,0:nc)
double precision, intent(inout) :: d(n_points,0:nd)
integer :: ib, ic, id, k, ipoint
if (nd < nb+nc) then
print *, nd, nb, nc
print *, irp_here, ': nd < nb+nc'
stop 1
endif
do ic = 0,nc
do ipoint=1, n_points
d(ipoint,ic) = d(ipoint,ic) + c(ipoint,ic) * b(ipoint,0)
enddo
enddo
do ib=1,nb
do ipoint=1, n_points
d(ipoint, ib) = d(ipoint, ib) + c(ipoint,0) * b(ipoint, ib)
enddo
do ic = 1,nc
do ipoint=1, n_points
d(ipoint, ib+ic) = d(ipoint, ib+ic) + c(ipoint,ic) * b(ipoint, ib)
enddo
enddo
enddo
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end
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subroutine add_poly(b,nb,c,nc,d,nd)
implicit none
BEGIN_DOC
! Add two polynomials
! D(t) += B(t)+C(t)
END_DOC
integer, intent(inout) :: nb, nc
integer, intent(out) :: nd
double precision, intent(in) :: b(0:nb), c(0:nc)
double precision, intent(out) :: d(0:nb+nc)
nd = nb+nc
integer :: ib, ic, id
do ib=0,max(nb,nc)
d(ib) = d(ib) + c(ib) + b(ib)
enddo
do while ( (d(nd) == 0.d0).and.(nd>=0) )
nd -= 1
if (nd < 0) then
exit
endif
enddo
end
subroutine add_poly_multiply(b,nb,cst,d,nd)
implicit none
BEGIN_DOC
! Add a polynomial multiplied by a constant
! D(t) += cst * B(t)
END_DOC
integer, intent(in) :: nb
integer, intent(inout) :: nd
double precision, intent(in) :: b(0:nb),cst
double precision, intent(inout) :: d(0:max(nb,nd))
nd = max(nd,nb)
if (nd /= -1) then
integer :: ib, ic, id
do ib=0,nb
d(ib) = d(ib) + cst*b(ib)
enddo
do while ( d(nd) == 0.d0 )
nd -= 1
if (nd < 0) then
exit
endif
enddo
endif
end
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subroutine recentered_poly2_v(P_new, lda, x_A, LD_xA, x_P, a, P_new2, ldb, x_B, x_Q, b, n_points)
BEGIN_DOC
! Recenter two polynomials
END_DOC
implicit none
integer, intent(in) :: a(3), b(3), n_points, lda, ldb, LD_xA
double precision, intent(in) :: x_A(LD_xA,3), x_P(n_points,3), x_B(3), x_Q(n_points,3)
double precision, intent(out) :: P_new(n_points,0:lda,3),P_new2(n_points,0:ldb,3)
double precision :: binom_func
integer :: i,j,k,l, minab(3), maxab(3),ipoint, xyz
double precision, allocatable :: pows_a(:,:), pows_b(:,:)
double precision :: fa, fb
maxab(1:3) = max(a(1:3),b(1:3))
minab(1:3) = max(min(a(1:3),b(1:3)),(/0,0,0/))
allocate( pows_a(n_points,-2:maxval(maxab)+4), pows_b(n_points,-2:maxval(maxab)+4) )
do xyz=1,3
if ((a(xyz)<0).or.(b(xyz)<0) ) cycle
do ipoint=1,n_points
pows_a(ipoint,0) = 1.d0
pows_a(ipoint,1) = (x_P(ipoint,xyz) - x_A(ipoint,xyz))
pows_b(ipoint,0) = 1.d0
pows_b(ipoint,1) = (x_Q(ipoint,xyz) - x_B(xyz))
enddo
do i = 2,maxab(xyz)
do ipoint=1,n_points
pows_a(ipoint,i) = pows_a(ipoint,i-1)*pows_a(ipoint,1)
pows_b(ipoint,i) = pows_b(ipoint,i-1)*pows_b(ipoint,1)
enddo
enddo
do ipoint=1,n_points
P_new (ipoint,0,xyz) = pows_a(ipoint,a(xyz))
P_new2(ipoint,0,xyz) = pows_b(ipoint,b(xyz))
enddo
do i = 1,min(minab(xyz),20)
fa = binom_transp(a(xyz)-i,a(xyz))
fb = binom_transp(b(xyz)-i,b(xyz))
do ipoint=1,n_points
P_new (ipoint,i,xyz) = fa * pows_a(ipoint,a(xyz)-i)
P_new2(ipoint,i,xyz) = fb * pows_b(ipoint,b(xyz)-i)
enddo
enddo
do i = minab(xyz)+1,min(a(xyz),20)
fa = binom_transp(a(xyz)-i,a(xyz))
do ipoint=1,n_points
P_new (ipoint,i,xyz) = fa * pows_a(ipoint,a(xyz)-i)
enddo
enddo
do i = minab(xyz)+1,min(b(xyz),20)
fb = binom_transp(b(xyz)-i,b(xyz))
do ipoint=1,n_points
P_new2(ipoint,i,xyz) = fb * pows_b(ipoint,b(xyz)-i)
enddo
enddo
do i = 21,a(xyz)
fa = binom_func(a(xyz),a(xyz)-i)
do ipoint=1,n_points
P_new (ipoint,i,xyz) = fa * pows_a(ipoint,a(xyz)-i)
enddo
enddo
do i = 21,b(xyz)
fb = binom_func(b(xyz),b(xyz)-i)
do ipoint=1,n_points
P_new2(ipoint,i,xyz) = fb * pows_b(ipoint,b(xyz)-i)
enddo
enddo
enddo
end subroutine recentered_poly2_v
! ---
subroutine recentered_poly2_v0(P_new, lda, x_A, LD_xA, x_P, a, n_points)
BEGIN_DOC
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!
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! Recenter two polynomials. Special case for b=(0,0,0)
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!
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! (x - A)^a (x - B)^0 = (x - P + P - A)^a (x - Q + Q - B)^0
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! = (x - P + P - A)^a
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!
END_DOC
implicit none
integer, intent(in) :: a(3), n_points, lda, LD_xA
double precision, intent(in) :: x_A(LD_xA,3), x_P(n_points,3)
!double precision, intent(in) :: x_B(3), x_Q(n_points,3)
double precision, intent(out) :: P_new(n_points,0:lda,3)
!double precision, intent(out) :: P_new2(n_points,3)
integer :: i, j, k, l, xyz, ipoint, maxab(3)
double precision :: fa
double precision, allocatable :: pows_a(:,:)
!double precision, allocatable :: pows_b(:,:)
double precision :: binom_func
maxab(1:3) = max(a(1:3), (/0,0,0/))
allocate(pows_a(n_points,-2:maxval(maxab)+4))
!allocate(pows_b(n_points,-2:maxval(maxab)+4))
do xyz = 1, 3
if(a(xyz) < 0) cycle
do ipoint = 1, n_points
pows_a(ipoint,0) = 1.d0
pows_a(ipoint,1) = (x_P(ipoint,xyz) - x_A(ipoint,xyz))
!pows_b(ipoint,0) = 1.d0
!pows_b(ipoint,1) = (x_Q(ipoint,xyz) - x_B(xyz))
enddo
do i = 2, maxab(xyz)
do ipoint = 1, n_points
pows_a(ipoint,i) = pows_a(ipoint,i-1) * pows_a(ipoint,1)
!pows_b(ipoint,i) = pows_b(ipoint,i-1) * pows_b(ipoint,1)
enddo
enddo
do ipoint = 1, n_points
P_new (ipoint,0,xyz) = pows_a(ipoint,a(xyz))
!P_new2(ipoint,xyz) = pows_b(ipoint,0)
enddo
do i = 1, min(a(xyz), 20)
fa = binom_transp(a(xyz)-i, a(xyz))
do ipoint = 1, n_points
P_new(ipoint,i,xyz) = fa * pows_a(ipoint,a(xyz)-i)
enddo
enddo
do i = 21, a(xyz)
fa = binom_func(a(xyz), a(xyz)-i)
do ipoint = 1, n_points
P_new(ipoint,i,xyz) = fa * pows_a(ipoint,a(xyz)-i)
enddo
enddo
enddo !xyz
deallocate(pows_a)
!deallocate(pows_b)
end subroutine recentered_poly2_v0
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subroutine recentered_poly2(P_new,x_A,x_P,a,P_new2,x_B,x_Q,b)
implicit none
BEGIN_DOC
! Recenter two polynomials
END_DOC
integer, intent(in) :: a,b
double precision, intent(in) :: x_A,x_P,x_B,x_Q
double precision, intent(out) :: P_new(0:a),P_new2(0:b)
double precision :: pows_a(-2:a+b+4), pows_b(-2:a+b+4)
double precision :: binom_func
integer :: i,j,k,l, minab, maxab
if ((a<0).or.(b<0) ) return
maxab = max(a,b)
minab = max(min(a,b),0)
pows_a(0) = 1.d0
pows_a(1) = (x_P - x_A)
pows_b(0) = 1.d0
pows_b(1) = (x_Q - x_B)
do i = 2,maxab
pows_a(i) = pows_a(i-1)*pows_a(1)
pows_b(i) = pows_b(i-1)*pows_b(1)
enddo
P_new (0) = pows_a(a)
P_new2(0) = pows_b(b)
do i = 1,min(minab,20)
P_new (i) = binom_transp(a-i,a) * pows_a(a-i)
P_new2(i) = binom_transp(b-i,b) * pows_b(b-i)
enddo
do i = minab+1,min(a,20)
P_new (i) = binom_transp(a-i,a) * pows_a(a-i)
enddo
do i = minab+1,min(b,20)
P_new2(i) = binom_transp(b-i,b) * pows_b(b-i)
enddo
do i = 101,a
P_new(i) = binom_func(a,a-i) * pows_a(a-i)
enddo
do i = 101,b
P_new2(i) = binom_func(b,b-i) * pows_b(b-i)
enddo
end
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subroutine pol_modif_center(A_center, B_center, iorder, A_pol, B_pol)
BEGIN_DOC
!
! Transform the pol centerd on A:
! [ \sum_i ax_i (x-x_A)^i ] [ \sum_j ay_j (y-y_A)^j ] [ \sum_k az_k (z-z_A)^k ]
! to a pol centered on B
! [ \sum_i bx_i (x-x_B)^i ] [ \sum_j by_j (y-y_B)^j ] [ \sum_k bz_k (z-z_B)^k ]
!
END_DOC
! useful for max_dim
include 'constants.include.F'
implicit none
integer, intent(in) :: iorder(3)
double precision, intent(in) :: A_center(3), B_center(3)
double precision, intent(in) :: A_pol(0:max_dim, 3)
double precision, intent(out) :: B_pol(0:max_dim, 3)
integer :: i, Lmax
do i = 1, 3
Lmax = iorder(i)
call pol_modif_center_x( A_center(i), B_center(i), Lmax, A_pol(0:Lmax, i), B_pol(0:Lmax, i) )
enddo
return
end subroutine pol_modif_center
subroutine pol_modif_center_x(A_center, B_center, iorder, A_pol, B_pol)
BEGIN_DOC
!
! Transform the pol centerd on A:
! [ \sum_i ax_i (x-x_A)^i ]
! to a pol centered on B
! [ \sum_i bx_i (x-x_B)^i ]
!
! bx_i = \sum_{j=i}^{iorder} ax_j (x_B - x_A)^(j-i) j! / [ i! (j-i)! ]
! = \sum_{j=i}^{iorder} ax_j (x_B - x_A)^(j-i) binom_func(j,i)
!
END_DOC
implicit none
integer, intent(in) :: iorder
double precision, intent(in) :: A_center, B_center
double precision, intent(in) :: A_pol(0:iorder)
double precision, intent(out) :: B_pol(0:iorder)
integer :: i, j
double precision :: fact_tmp, dx
double precision :: binom_func
dx = B_center - A_center
do i = 0, iorder
fact_tmp = 0.d0
do j = i, iorder
fact_tmp += A_pol(j) * binom_func(j, i) * dx**dble(j-i)
enddo
B_pol(i) = fact_tmp
enddo
return
end subroutine pol_modif_center_x
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double precision function F_integral(n,p)
BEGIN_DOC
! function that calculates the following integral
! \int_{\-infty}^{+\infty} x^n \exp(-p x^2) dx
END_DOC
implicit none
integer :: n
double precision :: p
integer :: i,j
double precision :: accu,sqrt_p,fact_ratio,tmp,fact
include 'constants.include.F'
if(n < 0)then
F_integral = 0.d0
endif
if(iand(n,1).ne.0)then
F_integral = 0.d0
return
endif
sqrt_p = 1.d0/dsqrt(p)
if(n==0)then
F_integral = sqpi * sqrt_p
return
endif
F_integral = sqpi * 0.5d0**n * sqrt_p**(n+1) * fact(n)/fact(shiftr(n,1))
end
double precision function rint(n,rho)
implicit none
BEGIN_DOC
!.. math::
!
! \int_0^1 dx \exp(-p x^2) x^n
!
END_DOC
include 'constants.include.F'
double precision :: rho,u,rint1,v,val0,rint_large_n,u_inv
integer :: n,k
double precision :: two_rho_inv
if(n.eq.0)then
if(rho == 0.d0)then
rint=1.d0
else
u_inv=1.d0/dsqrt(rho)
u=rho*u_inv
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rint=0.5d0*u_inv*sqpi*derf(u)
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endif
return
endif
if(rho.lt.1.d0)then
rint=rint1(n,rho)
else
if(n.le.20)then
u_inv=1.d0/dsqrt(rho)
if(rho.gt.80.d0)then
v=0.d0
else
v=dexp(-rho)
endif
u=rho*u_inv
two_rho_inv = 0.5d0*u_inv*u_inv
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val0=0.5d0*u_inv*sqpi*derf(u)
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rint=(val0-v)*two_rho_inv
do k=2,n
rint=(rint*dfloat(k+k-1)-v)*two_rho_inv
enddo
else
rint=rint_large_n(n,rho)
endif
endif
end
double precision function rint_sum(n_pt_out,rho,d1)
implicit none
BEGIN_DOC
! Needed for the calculation of two-electron integrals.
END_DOC
include 'constants.include.F'
integer, intent(in) :: n_pt_out
double precision, intent(in) :: rho,d1(0:n_pt_out)
double precision :: u,rint1,v,val0,rint_large_n,u_inv
integer :: n,k,i
double precision :: two_rho_inv, rint_tmp, di
if(rho < 1.d0)then
if(rho == 0.d0)then
rint_sum=d1(0)
else
u_inv=1.d0/dsqrt(rho)
u=rho*u_inv
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rint_sum=0.5d0*u_inv*sqpi*derf(u) *d1(0)
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endif
do i=2,n_pt_out,2
n = shiftr(i,1)
rint_sum = rint_sum + d1(i)*rint1(n,rho)
enddo
else
if(rho.gt.80.d0)then
v=0.d0
else
v=dexp(-rho)
endif
u_inv=1.d0/dsqrt(rho)
u=rho*u_inv
two_rho_inv = 0.5d0*u_inv*u_inv
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val0=0.5d0*u_inv*sqpi*derf(u)
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rint_sum=val0*d1(0)
rint_tmp=(val0-v)*two_rho_inv
di = 3.d0
do i=2,min(n_pt_out,40),2
rint_sum = rint_sum + d1(i)*rint_tmp
rint_tmp = (rint_tmp*di-v)*two_rho_inv
di = di+2.d0
enddo
do i=42,n_pt_out,2
n = shiftr(i,1)
rint_sum = rint_sum + d1(i)*rint_large_n(n,rho)
enddo
endif
end
double precision function hermite(n,x)
implicit none
BEGIN_DOC
! Hermite polynomial
END_DOC
integer :: n,k
double precision :: h0,x,h1,h2
h0=1.d0
if(n.eq.0)then
hermite=h0
return
endif
h1=x+x
if(n.eq.1)then
hermite=h1
return
endif
do k=1,n-1
h2=(x+x)*h1-dfloat(k+k)*h0
h0=h1
h1=h2
enddo
hermite=h2
end
double precision function rint_large_n(n,rho)
implicit none
BEGIN_DOC
! Version of rint for large values of n
END_DOC
integer :: n,k,l
double precision :: rho,u,accu,eps,t1,t2,fact,alpha_k,rajout,hermite
u=dsqrt(rho)
accu=0.d0
k=0
eps=1.d0
do while (eps.gt.1.d-15)
t1=1.d0
do l=0,k
t1=t1*(n+n+l+1.d0)
enddo
t2=0.d0
do l=0,k
t2=t2+(-1.d0)**l/(fact(l+1)*fact(k-l))
enddo
alpha_k=t2*fact(k+1)*fact(k)*(-1.d0)**k
alpha_k= alpha_k/t1
rajout=(-1.d0)**k*u**k*hermite(k,u)*alpha_k/fact(k)
accu=accu+rajout
eps=dabs(rajout)/accu
k=k+1
enddo
rint_large_n=dexp(-rho)*accu
end
double precision function rint1(n,rho)
implicit none
BEGIN_DOC
! Standard version of rint
END_DOC
integer, intent(in) :: n
double precision, intent(in) :: rho
double precision, parameter :: eps=1.d-15
double precision :: rho_tmp, diff
integer :: k
rint1=inv_int(n+n+1)
rho_tmp = 1.d0
do k=1,20
rho_tmp = -rho_tmp*rho
diff=rho_tmp*fact_inv(k)*inv_int(shiftl(k+n,1)+1)
rint1=rint1+diff
if (dabs(diff) > eps) then
cycle
endif
return
enddo
write(*,*)'pb in rint1 k too large!'
stop 1
end
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! ---
double precision function V_phi(n, m)
BEGIN_DOC
! Computes the angular $\phi$ part of the nuclear attraction integral:
!
! $\int_{0}^{2 \pi} \cos(\phi)^n \sin(\phi)^m d\phi$.
END_DOC
implicit none
integer, intent(in) :: n, m
integer :: i
double precision :: prod
double precision :: Wallis
prod = 1.d0
do i = 0, shiftr(n, 1)-1
prod = prod/ (1.d0 + dfloat(m+1)/dfloat(n-i-i-1))
enddo
V_phi = 4.d0 * prod * Wallis(m)
end function V_phi
! ---
double precision function V_theta(n, m)
BEGIN_DOC
! Computes the angular $\theta$ part of the nuclear attraction integral:
!
! $\int_{0}^{\pi} \cos(\theta)^n \sin(\theta)^m d\theta$
END_DOC
implicit none
include 'utils/constants.include.F'
integer, intent(in) :: n, m
integer :: i
double precision :: prod
double precision :: Wallis
V_theta = 0.d0
prod = 1.d0
do i = 0, shiftr(n, 1)-1
prod = prod / (1.d0 + dfloat(m+1)/dfloat(n-i-i-1))
enddo
V_theta = (prod + prod) * Wallis(m)
end function V_theta
! ---
double precision function Wallis(n)
BEGIN_DOC
! Wallis integral:
!
! $\int_{0}^{\pi} \cos(\theta)^n d\theta$.
END_DOC
implicit none
include 'utils/constants.include.F'
integer, intent(in) :: n
integer :: p
double precision :: fact
if(iand(n, 1) .eq. 0) then
Wallis = fact(shiftr(n, 1))
Wallis = pi * fact(n) / (dble(ibset(0_8, n)) * (Wallis + Wallis) * Wallis)
else
p = shiftr(n, 1)
Wallis = fact(p)
Wallis = dble(ibset(0_8, p+p)) * Wallis * Wallis / fact(p+p+1)
endif
end function Wallis
! ---