From 0ffd680076effb0d9cd7f76765363f3756bdc8d2 Mon Sep 17 00:00:00 2001
From: Christoph Groth <christoph.groth@cea.fr>
Date: Tue, 12 Feb 2013 16:12:09 +0100
Subject: [PATCH] minor bugfix: no longer allow hoppings between a site and
itself
---
kwant/builder.py | 2 ++
kwant/tests/test_builder.py | 4 +++-
2 files changed, 5 insertions(+), 1 deletion(-)
diff --git a/kwant/builder.py b/kwant/builder.py
index a4ba1f52..59cdf2b8 100644
--- a/kwant/builder.py
+++ b/kwant/builder.py
@@ -672,6 +672,8 @@ class Builder(object):
a, b = hopping
except:
raise KeyError(hopping)
+ if a == b:
+ raise KeyError(hopping)
if isinstance(value, HermConjOfFunc):
a, b = b, a
value = value.function
diff --git a/kwant/tests/test_builder.py b/kwant/tests/test_builder.py
index 44b73f88..cbb8e27b 100644
--- a/kwant/tests/test_builder.py
+++ b/kwant/tests/test_builder.py
@@ -114,7 +114,9 @@ def test_construction_and_indexing():
hoppings = [(gr(0, 0), gr(0, 1)),
(gr(0, 1), gr(1, 0)),
(gr(1, 0), gr(0, 0))]
- failing_hoppings = [(gr(0, 1), gr(7, 8)), (gr(12, 14), gr(0, 1))]
+ failing_hoppings = [(gr(0, 1), gr(0, 1)),
+ (gr(0, 1), gr(7, 8)),
+ (gr(12, 14), gr(0, 1))]
check_construction_and_indexing(sites, sites, hoppings, hoppings,
failing_hoppings)
--
GitLab