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module inifgn_m |
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use dimens_m, only: iim |
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IMPLICIT NONE |
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private iim |
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real sddu(iim), sddv(iim) ! SQRT(dx) |
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real unsddu(iim), unsddv(iim) |
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real eignfnu(iim, iim), eignfnv(iim, iim) |
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! eignfn eigenfunctions of the discrete laplacian |
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contains |
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SUBROUTINE inifgn(dv) |
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! From LMDZ4/libf/filtrez/inifgn.F, v 1.1.1.1 2004/05/19 12:53:09 |
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! H.Upadyaya, O.Sharma |
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USE dimens_m, ONLY: iim |
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USE dynetat0_m, ONLY: xprimu, xprimv |
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use nr_util, only: pi |
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use numer_rec_95, only: jacobi |
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real, intent(out):: dv(iim) |
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! Local: |
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REAL vec(iim, iim), vec1(iim, iim) |
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REAL du(iim) |
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real d(iim) |
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INTEGER i, j, k, nrot |
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EXTERNAL acc |
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!---------------------------------------------------------------- |
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sddv = sqrt(xprimv(:iim)) |
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sddu = sqrt(xprimu(:iim)) |
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unsddu = 1. / sddu |
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unsddv = 1. / sddv |
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DO j = 1, iim |
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DO i = 1, iim |
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vec(i, j) = 0. |
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vec1(i, j) = 0. |
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eignfnv(i, j) = 0. |
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eignfnu(i, j) = 0. |
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END DO |
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END DO |
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eignfnv(1, 1) = - 1. |
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eignfnv(iim, 1) = 1. |
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DO i = 1, iim - 1 |
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eignfnv(i+1, i+1) = - 1. |
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eignfnv(i, i+1) = 1. |
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END DO |
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DO j = 1, iim |
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DO i = 1, iim |
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eignfnv(i, j) = eignfnv(i, j) / (sddu(i) * sddv(j)) |
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END DO |
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END DO |
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DO j = 1, iim |
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DO i = 1, iim |
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eignfnu(i, j) = - eignfnv(j, i) |
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END DO |
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END DO |
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DO j = 1, iim |
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DO i = 1, iim |
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vec(i, j) = 0.0 |
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vec1(i, j) = 0.0 |
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DO k = 1, iim |
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vec(i, j) = vec(i, j) + eignfnu(i, k) * eignfnv(k, j) |
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vec1(i, j) = vec1(i, j) + eignfnv(i, k) * eignfnu(k, j) |
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END DO |
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END DO |
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END DO |
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CALL jacobi(vec, dv, eignfnv, nrot) |
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CALL acc(eignfnv, d, iim) |
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CALL eigen_sort(dv, eignfnv, iim, iim) |
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CALL jacobi(vec1, du, eignfnu, nrot) |
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CALL acc(eignfnu, d, iim) |
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CALL eigen_sort(du, eignfnu, iim, iim) |
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END SUBROUTINE inifgn |
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end module inifgn_m |