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jmc |
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C $Header: $ |
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C $Name: $ |
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dgoldberg |
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#include "CPP_OPTIONS.h" |
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! _RL FUNCTION SLOPE_LIMITER (num, denom) |
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_RL FUNCTION SLOPE_LIMITER (Cr) |
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! _RL num, denom |
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! _RL SLOPE_LIMITER |
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! _RL r |
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_RL Cr |
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! used for flux limiting in advective subroutines |
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! Van Leer limiter (source: Wikipedia!) |
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! if (denom .eq. 0.0) then |
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! SLOPE_LIMITER = 0.0 |
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! elseif (num*denom .le. 0.0) then |
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! SLOPE_LIMITER = 0.0 |
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! else |
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! r = num/denom |
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! SLOPE_LIMITER = (r+abs(r))/(1+abs(r)) |
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! endif |
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SLOPE_LIMITER = max(0.D0,max(min(1.D0,2.D0*Cr), |
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& min(2.D0,Cr))) |
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RETURN |
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jmc |
1.2 |
END |