NativeLayer: support None bias.

deepmd_utils/model_format.py

@@ -194,8 +194,8 @@ def deserialize(cls, data: dict) -> "NativeLayer":
         """
         return cls(
             w=data["@variables"]["w"],
-            b=data["@variables"]["b"],
-            idt=data.get("idt", None),
+            b=data["@variables"].get("b", None),
+            idt=data["@variables"].get("idt", None),
             activation_function=data["activation_function"],
             resnet=data.get("resnet", False),
         )
@@ -241,7 +241,7 @@ def call(self, x: np.ndarray) -> np.ndarray:
         np.ndarray
             The output.
         """
-        if self.w is None or self.b is None or self.activation_function is None:
+        if self.w is None or self.activation_function is None:
             raise ValueError("w, b, and activation_function must be set")
         if self.activation_function == "tanh":
             fn = np.tanh
@@ -251,7 +251,12 @@ def fn(x):
                 return x
         else:
             raise NotImplementedError(self.activation_function)
-        y = fn(np.matmul(x, self.w) + self.b)
+        y = (
+            np.matmul(x, self.w) + self.b
+            if self.b is not None
+            else np.matmul(x, self.w)
+        )
+        y = fn(y)
         if self.idt is not None:
             y *= self.idt
         if self.resnet and self.w.shape[1] == self.w.shape[0]:

source/tests/test_model_format_utils.py

@@ -1,4 +1,5 @@
 # SPDX-License-Identifier: LGPL-3.0-or-later
+import itertools
 import os
 import unittest
 from copy import (
@@ -8,16 +9,34 @@
 import numpy as np
 
 from deepmd_utils.model_format import (
+    NativeLayer,
     NativeNet,
     load_dp_model,
     save_dp_model,
 )
 
 
+class TestNativeLayer(unittest.TestCase):
+    def setUp(self) -> None:
+        self.w = np.full((2, 3), 3.0)
+        self.b = np.full((3,), 4.0)
+        self.idt = np.full((3,), 5.0)
+
+    def test_serialize_deserize(self):
+        for ww, bb, idt, activation_function, resnet in itertools.product(
+            [self.w], [self.b, None], [self.idt, None], ["tanh", "none"], [True, False]
+        ):
+            nl0 = NativeLayer(ww, bb, idt, activation_function, resnet)
+            nl1 = NativeLayer.deserialize(nl0.serialize())
+            inp = np.arange(self.w.shape[0])
+            np.testing.assert_allclose(nl0.call(inp), nl1.call(inp))
+
+
 class TestNativeNet(unittest.TestCase):
     def setUp(self) -> None:
-        self.w = np.full((3, 2), 3.0)
+        self.w = np.full((2, 3), 3.0)
         self.b = np.full((3,), 4.0)
+        self.idt = np.full((3,), 5.0)
 
     def test_serialize(self):
         network = NativeNet()