fix other side

Author: NoureldinYosri

test/test_value_array.py

@@ -274,11 +274,15 @@ def test_ufunc() -> None:
     x = np.float64(0.42)
     y = tu.GHz * np.arange(4)[1:]
 
-    assert (x * y).allclose(y * x)
-    assert (x / y).allclose(np.int64(1) / (y / x))
+    assert np.multiply(x, y).allclose(np.multiply(y, x))
+    assert np.divide(x, y).allclose(np.divide(np.int64(1), np.divide(y, x)))
 
     with pytest.raises(UnitMismatchError):
-        _ = x + y
+        _ = np.add(x, y)
+    with pytest.raises(UnitMismatchError):
+        _ = np.add(y, x)
 
     with pytest.raises(UnitMismatchError):
-        _ = x - y
+        _ = np.subtract(x, y)
+    with pytest.raises(UnitMismatchError):
+        _ = np.subtract(y, x)

tunits/core/cython/with_unit_value_array.pyx

@@ -95,14 +95,15 @@ class ValueArray(WithUnit):
 
     def __array_ufunc__(self, ufunc, method, *inputs, **kwargs):
         if method == "__call__":
+            is_value = isinstance(inputs[0], ValueArray)
             if ufunc == np.add:
-                return inputs[1].__radd__(inputs[0])
+                return inputs[0].__add__(inputs[1]) if is_value else inputs[1].__radd__(inputs[0])
             if ufunc == np.subtract:
-                return inputs[1].__rsub__(inputs[0])
+                return inputs[0].__sub__(inputs[1]) if is_value else inputs[1].__rsub__(inputs[0])
             if ufunc == np.multiply:
-                return inputs[1].__rmul__(inputs[0])
+                return inputs[0].__mul__(inputs[1]) if is_value else inputs[1].__rmul__(inputs[0])
             if ufunc == np.divide:
-                return inputs[1].__rtruediv__(inputs[0])
+                return inputs[0].__truediv__(inputs[1]) if is_value else inputs[1].__rtruediv__(inputs[0])
             if ufunc == np.power:
                 return inputs[0] ** inputs[1]
             if ufunc in [np.positive, np.negative, np.abs, np.fabs, np.conj]: