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commit
9ed77a0f9b
@ -411,3 +411,28 @@ subroutine lowercase(txt,n)
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enddo
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end
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subroutine v2_over_x(v,x,res)
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!BEGIN_DOC
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! Two by two diagonalization to avoid the divergence in v^2/x when x goes to 0
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!END_DOC
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implicit none
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double precision, intent(in) :: v, x
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double precision, intent(out) :: res
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double precision :: delta_E, tmp, val
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res = 0d0
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delta_E = x
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if (v == 0.d0) return
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val = 2d0 * v
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tmp = dsqrt(delta_E * delta_E + val * val)
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if (delta_E < 0.d0) then
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tmp = -tmp
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endif
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res = 0.5d0 * (tmp - delta_E)
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end
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