add reshape functions to backends

Author: sallen12

scoringrules/backend/base.py

@@ -310,3 +310,7 @@ def cov(self, x: "Array", rowvar: bool, bias: bool) -> "Array":
     @abc.abstractmethod
     def det(self, x: "Array") -> "Array":
         """Return the determinant of a matrix."""
+
+    @abc.abstractmethod
+    def reshape(self, x: "Array", shape: int | tuple[int, ...]) -> "Array":
+        """Reshape an array to a new ``shape``."""

scoringrules/backend/jax.py

@@ -280,6 +280,9 @@ def cov(self, x: "Array", rowvar: bool = True, bias: bool = False) -> "Array":
     def det(self, x: "Array") -> "Array":
         return jnp.linalg.det(x)
 
+    def reshape(self, x: "Array", shape: int | tuple[int, ...]) -> "Array":
+        return jnp.reshape(x, shape)
+
 
 if __name__ == "__main__":
     B = JaxBackend()

scoringrules/backend/numpy.py

@@ -276,6 +276,9 @@ def cov(self, x: "NDArray", rowvar: bool = True, bias: bool = False) -> "NDArray
     def det(self, x: "NDArray") -> "NDArray":
         return np.linalg.det(x)
 
+    def reshape(self, x: "NDArray", shape: int | tuple[int, ...]) -> "NDArray":
+        return np.reshape(x, shape=shape)
+
 
 class NumbaBackend(NumpyBackend):
     """Numba backend."""

scoringrules/backend/tensorflow.py

@@ -321,6 +321,9 @@ def cov(self, x: "Tensor", rowvar: bool = True, bias: bool = False) -> "Tensor":
     def det(self, x: "Tensor") -> "Tensor":
         return tf.linalg.det(x)
 
+    def reshape(self, x: "Tensor", shape: int | tuple[int, ...]) -> "Tensor":
+        return tf.reshape(x, shape)
+
 
 if __name__ == "__main__":
     B = TensorflowBackend()

scoringrules/backend/torch.py

@@ -300,3 +300,6 @@ def cov(self, x: "Tensor", rowvar: bool = True, bias: bool = False) -> "Tensor":
 
     def det(self, x: "Tensor") -> "Tensor":
         return torch.linalg.det(x)
+
+    def reshape(self, x: "Tensor", shape: int | tuple[int, ...]) -> "Tensor":
+        return torch.reshape(x, shape)