From 97ee612693818558e9ba8a56f5442ebd3e97b2e9 Mon Sep 17 00:00:00 2001
From: Doug Shi-Dong <doug.shidong@gmail.com>
Date: Thu, 26 Sep 2019 00:31:07 -0400
Subject: [PATCH] Fix Manifold get_new_point()

The weights can be negative, we simply want to avoid dividing by 0.
---
 source/grid/manifold.cc | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/source/grid/manifold.cc b/source/grid/manifold.cc
index 3f4a1217ce..5072c095af 100644
--- a/source/grid/manifold.cc
+++ b/source/grid/manifold.cc
@@ -95,7 +95,7 @@ Manifold<dim, spacedim>::get_new_point(
   for (unsigned int i = 1; i < n_points; ++i)
     {
       double weight = 0.0;
-      if ((weights[permutation[i]] + w) < tol)
+      if (std::abs(weights[permutation[i]] + w) < tol)
         weight = 0.0;
       else
         weight = w / (weights[permutation[i]] + w);
-- 
2.39.5