Add ValueArray.unique (#70)

Add a performant unique method.

Author: NoureldinYosri

test/test_value_array.py

@@ -286,3 +286,10 @@ def test_ufunc() -> None:
         _ = np.subtract(x, y)
     with pytest.raises(UnitMismatchError):
         _ = np.subtract(y, x)
+
+
+def test_unique() -> None:
+    xs = np.array([3.7, 0.9, 0.9, 4.3, 3.7])
+    unit = tu.MHz
+    v_arr = xs * unit
+    assert np.array_equal(v_arr.unique(), np.unique(xs) * unit)

tunits/core/__init__.pyi

@@ -334,6 +334,7 @@ class ValueArray(Generic[ValueType2], WithUnit):
     def to_proto(self, msg: tunits_pb2.ValueArray | None = None) -> tunits_pb2.ValueArray: ...
     def __init__(self, data: Any, unit: Any = None) -> None: ...
     def allclose(self, other: ValueArray | Value, *args: Any, **kwargs: float) -> bool: ...
+    def unique(self: ArrayType) -> ArrayType: ...
     def __array__(self, dtype: DTypeLike = None) -> NDArray[Any]: ...
     def __array_wrap__(self, out_arr: NDArray[Any], context: Any = None) -> NDArray[Any]: ...
     def __copy__(self: ArrayType) -> ArrayType: ...

tunits/core/cython/with_unit_value_array.pyx

@@ -150,6 +150,9 @@ class ValueArray(WithUnit):
     def allclose(WithUnit self, other, *args, **kw) -> bool:
         return np.allclose(self.value, other[self.unit], *args, **kw)
 
+    def unique(WithUnit self):
+        return self.__with_value(np.unique(self.value))
+
     @classmethod
     def from_proto(cls: type[T], msg: 'tunits_pb2.ValueArray') -> T:
         return cls(_ndarray_from_proto(msg), _proto_to_units(msg.units))