From f2d2f3b7198ced2fff6b05b131830c75fdc675d0 Mon Sep 17 00:00:00 2001
From: Martin Trapp <trapp.martin@gmail.com>
Date: Fri, 17 Nov 2017 16:17:22 +0100
Subject: [PATCH] bug fix in randindex

---
 src/randindex.jl | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/src/randindex.jl b/src/randindex.jl
index 008e37cc..733f5bf1 100644
--- a/src/randindex.jl
+++ b/src/randindex.jl
@@ -26,7 +26,11 @@ function randindex(c1,c2)
 
     if t1 == nc
         # avoid division by zero; if k=1, define Rand = 0
-        ARI = 0
+        if n == 1
+            ARI = 0.
+        else
+            ARI = 1.
+        end
     else
         # adjusted Rand - Hubert & Arabie 1985
         ARI = (A-nc)/(t1-nc)