added test for extracting constant with math operators

src/test/py/test_read_math_function.py

@@ -44,6 +44,8 @@ class read_function(unittest.TestCase):
         self.assertEqual(extract_constant("42x-5"), ["-5", "42x"])
     def test_extraction_linear_function_no_constant(self):
         self.assertEqual(extract_constant("42x"), ["0", "42x"])
+    def test_extraction_linear_function_constant_with_math_operators(self):
+        self.assertEqual(extract_constant("42x+42^(2)+1-3*4/3"), ["42^(2)+1-3*4/3", "42x"])
 
 if __name__ == '__main__':
     unittest.main()