From fa42eec6cb199805f09ca7d79534770ce34abe66 Mon Sep 17 00:00:00 2001
From: Tim Holy <tim.holy@gmail.com>
Date: Sun, 7 May 2017 05:35:41 -0500
Subject: [PATCH] Test for nans in cost matrix

If the cost matrix has nans, munkres goes into an endless loop. Better to throw immediately.
---
 src/Munkres.jl   | 1 +
 test/runtests.jl | 4 ++++
 2 files changed, 5 insertions(+)

diff --git a/src/Munkres.jl b/src/Munkres.jl
index 1d1740d..e4a2896 100644
--- a/src/Munkres.jl
+++ b/src/Munkres.jl
@@ -60,6 +60,7 @@ function munkres(cost_matrix)
     # and by and Yi Cao's surprisingly fast matlab version,
     # http://mathworks.com/matlabcentral/fileexchange/20328-munkres-assignment-algorithm
 
+    any(isnan, cost_matrix) && error("cost matrix cannot have NaNs")
     n,m = size(cost_matrix)
     flipped = false
     if n > m
diff --git a/test/runtests.jl b/test/runtests.jl
index 0395eb0..7fa0f4b 100644
--- a/test/runtests.jl
+++ b/test/runtests.jl
@@ -103,3 +103,7 @@ tst = [351.0 300.0 662.0 337.0 384.0 935.0 650.0 446.0 57.0 295.0 168.0 398.0 81
 p = [9, 6, 18, 3, 4, 17, 16, 7, 13, 20]
 
 @test munkres(tst) == p
+
+@test_throws ErrorException munkres(fill(NaN, (3,3)))
+
+nothing