From c54453ae42008f600a9d17a11158485ed137565a Mon Sep 17 00:00:00 2001
From: Andreas Lauser <and@poware.org>
Date: Mon, 13 Feb 2012 10:22:38 +0000
Subject: [PATCH] math.hh: fix stupid mistake in invertCubicPolynomial()
git-svn-id: svn://svn.iws.uni-stuttgart.de/DUMUX/dumux/trunk@7728 2fb0f335-1f38-0410-981e-8018bf24f1b0
---
dumux/common/math.hh | 16 ++++++++--------
1 file changed, 8 insertions(+), 8 deletions(-)
diff --git a/dumux/common/math.hh b/dumux/common/math.hh
index 378a980f97..2d83bb7f3a 100644
--- a/dumux/common/math.hh
+++ b/dumux/common/math.hh
@@ -247,15 +247,15 @@ int invertCubicPolynomial(SolContainer *sol,
// t^3 + p*t = 0 = t*(t^2 + p),
//
// i. e. roots at t = 0, t^2 + p = 0
- sol[0] = 0.0 - b/3;
- if (p > 0)
+ if (p > 0) {
+ sol[0] = 0.0 - b/3;
return 1; // only a single real root at t=0
- // two additional real roots at t = sqrt(-p) and t = -sqrt(-p)
- sol[1] = std::sqrt(-p) - b/3;
- sol[2] = -sol[1];
+ }
- // sort the result
- std::sort(sol, sol + 3);
+ // two additional real roots at t = sqrt(-p) and t = -sqrt(-p)
+ sol[0] = -std::sqrt(-p) - b/3;;
+ sol[1] = 0.0 - b/3;
+ sol[2] = std::sqrt(-p) - b/3;
return 3;
}
@@ -280,7 +280,7 @@ int invertCubicPolynomial(SolContainer *sol,
//
// Now, substituting u^3 = w yields
//
- // w^2 + q*w - p^3/27
+ // w^2 + q*w - p^3/27 = 0
//
// This is a quadratic equation with the solutions
//
--
GitLab