From 4de6e9d3e4d528c287a0e2a5e268deae917ec530 Mon Sep 17 00:00:00 2001
From: Zeno Rogue <zeno@attnam.com>
Date: Sat, 13 Jan 2018 19:21:08 +0100
Subject: [PATCH] warning when inverting a singular matrix

---
 hyperpoint.cpp | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/hyperpoint.cpp b/hyperpoint.cpp
index 1d8b607e..df6a4cfa 100644
--- a/hyperpoint.cpp
+++ b/hyperpoint.cpp
@@ -384,7 +384,13 @@ transmatrix inverse(const transmatrix& T) {
   
   ld d = det(T);
   transmatrix T2;
-  if(d == 0) return T2;
+  if(d == 0) { 
+    printf("Warning: inverting a singular matrix\n");
+    display(T);
+    display(T2);
+    T2 = Id; 
+    return T2; 
+    }
   
   for(int i=0; i<3; i++) 
   for(int j=0; j<3; j++)