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module regr3_lint_m |
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|
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implicit none |
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|
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interface regr3_lint |
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! Each procedure regrids by linear interpolation. |
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! The regridding operation is done on the third dimension of the |
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! input array. |
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! The difference betwwen the procedures is the rank of the first argument. |
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module procedure regr33_lint |
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end interface |
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|
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private |
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public regr3_lint |
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|
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contains |
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|
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function regr33_lint(vs, xs, xt) result(vt) |
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|
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! "vs" has rank 3. |
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|
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use numer_rec, only: assert_eq, hunt |
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|
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real, intent(in):: vs(:, :, :) |
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! (values of the function at source points "xs") |
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|
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real, intent(in):: xs(:) |
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! (abscissas of points in source grid, in strictly monotonic order) |
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|
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real, intent(in):: xt(:) |
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! (abscissas of points in target grid) |
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|
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real vt(size(vs, 1), size(vs, 2), size(xt)) |
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! (values of the function on the target grid) |
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|
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! Variables local to the procedure: |
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integer is, it, ns |
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integer is_b ! "is" bound between 1 and "ns - 1" |
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|
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!-------------------------------------- |
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|
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ns = assert_eq(size(vs, 3), size(xs), "regr33_lint ns") |
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|
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is = -1 ! go immediately to bisection on first call to "hunt" |
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|
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do it = 1, size(xt) |
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call hunt(xs, xt(it), is) |
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is_b = min(max(is, 1), ns - 1) |
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vt(:, :, it) = ((xs(is_b+1) - xt(it)) * vs(:, :, is_b) & |
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+ (xt(it) - xs(is_b)) * vs(:, :, is_b+1)) / (xs(is_b+1) - xs(is_b)) |
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end do |
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|
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end function regr33_lint |
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|
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end module regr3_lint_m |