make consistency.Approx repr consistent with class behavior

sarpy/consistency/consistency.py

@@ -418,25 +418,26 @@ def __lt__(self, rhs):
         return self.__le__(rhs)
 
     def __le__(self, rhs):
-        return np.all(np.logical_or(np.less(self.value, rhs),
-                                    np.isclose(self.value, rhs, rtol=self.rtol, atol=self.atol)))
+        return np.all(np.logical_or(np.less(self.value, rhs), self._isclose(rhs)))
 
     def __eq__(self, rhs):
-        return np.all(np.isclose(self.value, rhs, rtol=self.rtol, atol=self.atol))
+        return np.all(self._isclose(rhs))
 
     def __ne__(self, rhs):
         return not self.__eq__(rhs)
 
     def __ge__(self, rhs):
-        return np.all(np.logical_or(np.greater(self.value, rhs),
-                                    np.isclose(self.value, rhs, rtol=self.rtol, atol=self.atol)))
+        return np.all(np.logical_or(np.greater(self.value, rhs), self._isclose(rhs)))
 
     def __gt__(self, rhs):
         return self.__ge__(rhs)
 
     def __repr__(self):
-        tol = np.maximum(self.atol, np.asarray(self.value) * self.rtol)
-        return "{} +/- {}".format(self.value, tol)
+        tol = self.atol + np.abs(np.asarray(self.value)) * self.rtol
+        return f"{self.value} ± {tol}"
+
+    def _isclose(self, rhs):
+        return np.isclose(rhs, self.value, rtol=self.rtol, atol=self.atol)
 
 
 def in_color(string, *color):

tests/consistency/test_consistency.py

@@ -161,7 +161,7 @@ def test_invalid(dummycon):
 
 
 def test_approx():
-    apx = con.Approx(10.0, atol=.1)
+    apx = con.Approx(10.0, atol=.1, rtol=0)
     assert apx == 10.0
     assert apx == 10.01
     assert not apx != 10.01
@@ -171,4 +171,4 @@ def test_approx():
     assert not apx <= 0
     assert apx < 10.01
     assert apx <= 10.01
-    assert repr(apx) == "10.0 +/- 0.1"
+    assert repr(apx) == "10.0 ± 0.1"