Sources/filtrez/inifgn.f

module inifgn_m

  use dimens_m, only: iim

  IMPLICIT NONE

  private iim

  real sddu(iim), sddv(iim) ! SQRT(dx / di)
  real unsddu(iim), unsddv(iim)

  real eignfnu(iim, iim), eignfnv(iim, iim)
  ! eigenfunctions of the discrete laplacian

contains

  SUBROUTINE inifgn(dv)

    ! From LMDZ4/libf/filtrez/inifgn.F, v 1.1.1.1 2004/05/19 12:53:09

    ! H. Upadyaya, O. Sharma 

    use acc_m, only: acc 
    USE dimens_m, ONLY: iim
    USE dynetat0_m, ONLY: xprimu, xprimv
    use nr_util, only: pi
    use numer_rec_95, only: jacobi, eigsrt

    real, intent(out):: dv(:) ! (iim) eigenvalues sorted in descending order

    ! Local:
    REAL vec(iim, iim), vec1(iim, iim)
    REAL du(iim)
    INTEGER i, j, k, nrot

    !----------------------------------------------------------------

    print *, "Call sequence information: inifgn"

    sddv = sqrt(xprimv(:iim))
    sddu = sqrt(xprimu(:iim))
    unsddu = 1. / sddu
    unsddv = 1. / sddv

    DO j = 1, iim
       DO i = 1, iim
          vec(i, j) = 0.
          vec1(i, j) = 0.
          eignfnv(i, j) = 0.
          eignfnu(i, j) = 0.
       END DO
    END DO

    eignfnv(1, 1) = - 1.
    eignfnv(iim, 1) = 1.
    DO i = 1, iim - 1
       eignfnv(i+1, i+1) = - 1.
       eignfnv(i, i+1) = 1.
    END DO

    DO j = 1, iim
       DO i = 1, iim
          eignfnv(i, j) = eignfnv(i, j) / (sddu(i) * sddv(j))
       END DO
    END DO

    DO j = 1, iim
       DO i = 1, iim
          eignfnu(i, j) = - eignfnv(j, i)
       END DO
    END DO

    DO j = 1, iim
       DO i = 1, iim
          vec(i, j) = 0.0
          vec1(i, j) = 0.0
          DO k = 1, iim
             vec(i, j) = vec(i, j) + eignfnu(i, k) * eignfnv(k, j)
             vec1(i, j) = vec1(i, j) + eignfnv(i, k) * eignfnu(k, j)
          END DO
       END DO
    END DO

    CALL jacobi(vec, dv, eignfnv, nrot)
    CALL acc(eignfnv)
    CALL eigsrt(dv, eignfnv)

    CALL jacobi(vec1, du, eignfnu, nrot)
    CALL acc(eignfnu)
    CALL eigsrt(du, eignfnu)

  END SUBROUTINE inifgn

end module inifgn_m
1	guez	113	module inifgn_m
2	guez	3
3	guez	140	use dimens_m, only: iim
4
5	guez	113	IMPLICIT NONE
6	guez	3
7	guez	140	private iim
8
9	guez	151	real sddu(iim), sddv(iim) ! SQRT(dx / di)
10	guez	140	real unsddu(iim), unsddv(iim)
11
12			real eignfnu(iim, iim), eignfnv(iim, iim)
13	guez	143	! eigenfunctions of the discrete laplacian
14	guez	140
15	guez	113	contains
16	guez	3
17	guez	113	SUBROUTINE inifgn(dv)
18	guez	3
19	guez	113	! From LMDZ4/libf/filtrez/inifgn.F, v 1.1.1.1 2004/05/19 12:53:09
20	guez	3
21	guez	143	! H. Upadyaya, O. Sharma
22	guez	3
23	guez	143	use acc_m, only: acc
24	guez	113	USE dimens_m, ONLY: iim
25	guez	139	USE dynetat0_m, ONLY: xprimu, xprimv
26	guez	140	use nr_util, only: pi
27	guez	143	use numer_rec_95, only: jacobi, eigsrt
28	guez	3
29	guez	151	real, intent(out):: dv(:) ! (iim) eigenvalues sorted in descending order
30	guez	81
31	guez	113	! Local:
32			REAL vec(iim, iim), vec1(iim, iim)
33			REAL du(iim)
34	guez	140	INTEGER i, j, k, nrot
35	guez	81
36	guez	113	!----------------------------------------------------------------
37	guez	81
38	guez	151	print *, "Call sequence information: inifgn"
39
40	guez	140	sddv = sqrt(xprimv(:iim))
41			sddu = sqrt(xprimu(:iim))
42			unsddu = 1. / sddu
43			unsddv = 1. / sddv
44	guez	81
45	guez	113	DO j = 1, iim
46			DO i = 1, iim
47			vec(i, j) = 0.
48			vec1(i, j) = 0.
49			eignfnv(i, j) = 0.
50			eignfnu(i, j) = 0.
51			END DO
52			END DO
53	guez	81
54	guez	140	eignfnv(1, 1) = - 1.
55	guez	113	eignfnv(iim, 1) = 1.
56	guez	140	DO i = 1, iim - 1
57			eignfnv(i+1, i+1) = - 1.
58	guez	113	eignfnv(i, i+1) = 1.
59	guez	81	END DO
60	guez	140
61	guez	113	DO j = 1, iim
62			DO i = 1, iim
63	guez	140	eignfnv(i, j) = eignfnv(i, j) / (sddu(i) * sddv(j))
64	guez	113	END DO
65	guez	81	END DO
66	guez	140
67	guez	113	DO j = 1, iim
68			DO i = 1, iim
69	guez	140	eignfnu(i, j) = - eignfnv(j, i)
70	guez	113	END DO
71			END DO
72	guez	81
73	guez	113	DO j = 1, iim
74			DO i = 1, iim
75			vec(i, j) = 0.0
76			vec1(i, j) = 0.0
77			DO k = 1, iim
78	guez	140	vec(i, j) = vec(i, j) + eignfnu(i, k) * eignfnv(k, j)
79			vec1(i, j) = vec1(i, j) + eignfnv(i, k) * eignfnu(k, j)
80	guez	113	END DO
81			END DO
82	guez	81	END DO
83
84	guez	132	CALL jacobi(vec, dv, eignfnv, nrot)
85	guez	143	CALL acc(eignfnv)
86			CALL eigsrt(dv, eignfnv)
87	guez	81
88	guez	132	CALL jacobi(vec1, du, eignfnu, nrot)
89	guez	143	CALL acc(eignfnu)
90			CALL eigsrt(du, eignfnu)
91	guez	81
92	guez	113	END SUBROUTINE inifgn
93	guez	81
94	guez	113	end module inifgn_m