diff --git a/TODO b/TODO
index 95787836..87554027 100644
--- a/TODO
+++ b/TODO
@@ -1,6 +1,12 @@
 
 - python:
 
+	- this is very annoying:
+
+		 real = im.complexget(Vips.OperationComplexget.REAL)
+
+	  define im.real() and im.imag()
+
 	- could import like this:
 
 		from gi.repository import Vips 
diff --git a/python/test_arithmetic.py b/python/test_arithmetic.py
index 668ef323..258c2439 100755
--- a/python/test_arithmetic.py
+++ b/python/test_arithmetic.py
@@ -264,5 +264,47 @@ class TestArithmetic(unittest.TestCase):
 
     # test the rest of VipsArithmetic
 
+    def test_avg(self):
+        im = Vips.Image.black(50, 100)
+        test = im.insert(im + 100, 50, 0, expand = True)
+
+        test.write_to_file("x.v")
+
+        for fmt in all_formats:
+            self.assertAlmostEqual(test.cast(fmt).avg(), 50)
+
+    def test_polar(self):
+        im = Vips.Image.black(100, 100) + 100
+        im = im.complexform(im)
+
+        im = im.complex(Vips.OperationComplex.POLAR)
+
+        real = im.complexget(Vips.OperationComplexget.REAL)
+        self.assertAlmostEqual(real.avg(), 100 * 2 ** 0.5)
+        imag = im.complexget(Vips.OperationComplexget.IMAG)
+        self.assertAlmostEqual(imag.avg(), 45)
+
+    def test_rect(self):
+        im = Vips.Image.black(100, 100)
+        im = (im + 100 * 2 ** 0.5).complexform(im + 45)
+
+        im = im.complex(Vips.OperationComplex.RECT)
+
+        real = im.complexget(Vips.OperationComplexget.REAL)
+        self.assertAlmostEqual(real.avg(), 100)
+        imag = im.complexget(Vips.OperationComplexget.IMAG)
+        self.assertAlmostEqual(imag.avg(), 100)
+
+    def test_conjugate(self):
+        im = Vips.Image.black(100, 100) + 100
+        im = im.complexform(im)
+
+        im = im.complex(Vips.OperationComplex.CONJ)
+
+        real = im.complexget(Vips.OperationComplexget.REAL)
+        self.assertAlmostEqual(real.avg(), 100)
+        imag = im.complexget(Vips.OperationComplexget.IMAG)
+        self.assertAlmostEqual(imag.avg(), -100)
+
 if __name__ == '__main__':
     unittest.main()