Make one hot encoder serialisable (#880)

CITATION.cff

@@ -30,6 +30,6 @@ authors:
 - family-names: "Picheny"
   given-names: "Victor"
 title: "Trieste"
-version: 4.2.0
-date-released: 2024-09-20
+version: 4.2.1
+date-released: 2024-10-11
 url: "https://github.com/secondmind-labs/trieste"

tests/unit/test_space.py

@@ -1830,7 +1830,7 @@ def test_categorical_search_space_one_hot_encoding(
         pytest.param(
             CategoricalSearchSpace(["Y", "N"]),
             tf.constant([[0], [2], [1]]),
-            ValueError,
+            InvalidArgumentError,
             id="Out of range binary input value",
         ),
         pytest.param(
@@ -1842,7 +1842,7 @@ def test_categorical_search_space_one_hot_encoding(
         pytest.param(
             CategoricalSearchSpace([["R", "G", "B"], ["Y", "N"]]),
             tf.constant([[0], [1], [1]]),
-            ValueError,
+            InvalidArgumentError,
             id="Wrong input shape",
         ),
     ],

trieste/VERSION

@@ -1 +1 @@
-4.2.0
+4.2.1

trieste/space.py

@@ -656,17 +656,12 @@ def one_hot_encoder(self) -> EncoderFunction:
 
         def binary_encoder(x: TensorType) -> TensorType:
             # no need to one-hot encode binary categories (but we should still validate)
-            if tf.reduce_any((x != 0) & (x != 1)):
-                raise ValueError(f"Invalid values {tf.boolean_mask(x, ((x != 0) & (x != 1)))}")
+            tf.debugging.Assert(tf.reduce_all((x == 0) | (x == 1)), [tf.constant([])])
             return x
 
         def encoder(x: TensorType) -> TensorType:
             flat_x, unflatten = flatten_leading_dims(x)
-            if flat_x.shape[-1] != len(self.tags):
-                raise ValueError(
-                    "Invalid input for one-hot encoding: "
-                    f"expected {len(self.tags)} tags, got {flat_x.shape[-1]}"
-                )
+            tf.debugging.assert_equal(flat_x.shape[-1], len(self.tags))
             columns = tf.split(flat_x, flat_x.shape[-1], axis=1)
             encoders = [
                 (

versions.json

@@ -4,8 +4,8 @@
     "url": "https://secondmind-labs.github.io/trieste/develop/"
   },
   {
-    "version": "4.2.0",
-    "url": "https://secondmind-labs.github.io/trieste/4.2.0/"
+    "version": "4.2.1",
+    "url": "https://secondmind-labs.github.io/trieste/4.2.1/"
   },
   {
     "version": "4.1.0",