diff --git a/ImageD11/sym_u.py b/ImageD11/sym_u.py
index b0c54165..634ebc6d 100644
--- a/ImageD11/sym_u.py
+++ b/ImageD11/sym_u.py
@@ -142,7 +142,7 @@ def rhombohedralP():
 
 def tetragonal():
     """ P4 75"""
-    return generate_group ( "-y,x,z", "-x,-y,z" )
+    return generate_group ( "-y,x,z", "-x,y,-z" )
     
 def orthorhombic():
     """ P222 16 """
@@ -158,7 +158,7 @@ def monoclinic_b():
     return generate_group("-x,y,-z" )
 
 def triclinic():
-    return generate_group("-x,-y,-z" )
+    return generate_group("x, y, z" )
 
 
 def find_uniq_u(u, grp, debug=0, func=np.trace):
diff --git a/test/run_tests.py b/test/run_tests.py
index 0cb59d22..52bbc357 100644
--- a/test/run_tests.py
+++ b/test/run_tests.py
@@ -5,6 +5,7 @@
 sys.path.insert(0,".")
 
 modules = [
+    "test_sym_u",
     "test_cImageD11",
     "gv_general.test_gv_general",
     "testcolumnfile",
diff --git a/test/test_sym_u.py b/test/test_sym_u.py
new file mode 100644
index 00000000..bc361789
--- /dev/null
+++ b/test/test_sym_u.py
@@ -0,0 +1,42 @@
+
+
+import ImageD11.sym_u
+import unittest
+
+class testsyms( unittest.TestCase ):
+
+    def test_cubic(self):
+        c = ImageD11.sym_u.cubic()
+        assert len(c.group) == 24
+
+    def test_hexagonal(self):
+        c = ImageD11.sym_u.hexagonal()
+        assert len(c.group) == 12
+
+    def test_tetragonal(self):
+        c = ImageD11.sym_u.tetragonal()
+        assert len(c.group) == 8
+
+    def test_orthorhombic(self):
+        c = ImageD11.sym_u.orthorhombic()
+        assert len(c.group) == 4
+
+    def test_monoclinic(self):
+        c = ImageD11.sym_u.monoclinic_a()
+        assert len(c.group) == 2
+        c = ImageD11.sym_u.monoclinic_b()
+        assert len(c.group) == 2
+        c = ImageD11.sym_u.monoclinic_c()
+        assert len(c.group) == 2
+
+    def test_triclinic(self):
+        c = ImageD11.sym_u.triclinic()
+        assert len(c.group) == 1
+
+        
+
+if __name__=="__main__":
+    unittest.main()
+
+        
+