Require PyTorch>=2.0.0

Author: lululxvi

README.md

@@ -74,7 +74,7 @@ DeepXDE requires one of the following backend-specific dependencies to be instal
 
 - TensorFlow 1.x: [TensorFlow](https://www.tensorflow.org)>=2.7.0
 - TensorFlow 2.x: [TensorFlow](https://www.tensorflow.org)>=2.3.0, [TensorFlow Probability](https://www.tensorflow.org/probability)>=0.11.0
-- PyTorch: [PyTorch](https://pytorch.org)>=1.9.0
+- PyTorch: [PyTorch](https://pytorch.org)>=2.0.0
 - JAX: [JAX](https://jax.readthedocs.io), [Flax](https://flax.readthedocs.io), [Optax](https://optax.readthedocs.io)
 - PaddlePaddle: [PaddlePaddle](https://www.paddlepaddle.org.cn/en)>=2.6.0
 

deepxde/backend/pytorch/tensor.py

@@ -4,8 +4,8 @@
 import torch
 
 
-if Version(torch.__version__) < Version("1.9.0"):
-    raise RuntimeError("DeepXDE requires PyTorch>=1.9.0.")
+if Version(torch.__version__) < Version("2.0.0"):
+    raise RuntimeError("DeepXDE requires PyTorch>=2.0.0.")
 
 # To write device-agnostic (CPU or GPU) code, a common pattern is to first determine
 # torch.device and then use it for all the tensors.

docs/user/installation.rst

@@ -14,7 +14,7 @@ DeepXDE requires one of the following backend-specific dependencies to be instal
 
     - For TensorFlow 2.16+ with Keras 3, refer to `the instruction <https://github.com/tensorflow/probability/releases/tag/v0.24.0>`_ for installing TensorFlow Probability.
 
-- PyTorch: `PyTorch <https://pytorch.org>`_>=1.9.0
+- PyTorch: `PyTorch <https://pytorch.org>`_>=2.0.0
 - JAX: `JAX <https://jax.readthedocs.io>`_, `Flax <https://flax.readthedocs.io>`_, `Optax <https://optax.readthedocs.io>`_
 - PaddlePaddle: `PaddlePaddle <https://www.paddlepaddle.org.cn/en>`_>=2.6.0
 
@@ -124,7 +124,7 @@ Export ``DDE_BACKEND`` as ``pytorch`` to specify PyTorch backend. In addition, i
 .. code:: python
 
     if torch.cuda.is_available():
-        torch.set_default_tensor_type(torch.cuda.FloatTensor)
+        torch.set_default_device("cuda")
 
 JAX backend
 ```````````