From 7937635ca25e8d2a82ddc5e89bfbe0ae3ba0e429 Mon Sep 17 00:00:00 2001
From: Fabian Joswig <fabian.joswig@ed.ac.uk>
Date: Mon, 6 Dec 2021 15:02:15 +0000
Subject: [PATCH] feat: check for name doublers in Obs.__init__ optimized

---
 pyerrors/obs.py | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/pyerrors/obs.py b/pyerrors/obs.py
index c1fcc8ca..38faa276 100644
--- a/pyerrors/obs.py
+++ b/pyerrors/obs.py
@@ -74,8 +74,10 @@ class Obs:
             if idl is not None:
                 if len(idl) != len(names):
                     raise Exception('Length of idl incompatible with samples and names.')
-            if len(names) != len(set(names)):
-                raise Exception('names are not unique.')
+            name_length = len(names)
+            if name_length > 1:
+                if name_length != len(set(names)):
+                    raise Exception('names are not unique.')
             if not all(isinstance(x, str) for x in names):
                 raise TypeError('All names have to be strings.')
             if min(len(x) for x in samples) <= 4: