Add clear() for forward-mode autodiff #1212

	name: build

	on:
	pull_request:
	push:
	branches:
	- master
	workflow_dispatch:

	concurrency:
	# Skip intermediate builds: always.
	# Cancel intermediate builds: only if it is a pull request build.
	group: ${{ github.workflow }}-${{ github.ref }}
	cancel-in-progress: ${{ startsWith(github.ref, 'refs/pull/') }}

	jobs:
	import:
	runs-on: ${{ matrix.os }}
	strategy:
	fail-fast: false
	matrix:
	python-version: ["3.9", "3.10", "3.11"]
	os: [ubuntu-latest, macos-latest, windows-latest]

	steps:
	- uses: actions/checkout@v3

	- uses: actions/setup-python@v4
	with:
	python-version: ${{ matrix.python-version }}

	- name: Install DeepXDE with requirements
	run: python -m pip install -e .

	- name: List environment
	run: python -m pip freeze

	- name: Test build with TensorFlow v1
	env:
	DDE_BACKEND: tensorflow.compat.v1
	run: \|
	python -m pip install tensorflow
	python -c "import deepxde"

	- name: Test build with TensorFlow
	env:
	DDE_BACKEND: tensorflow
	run: \|
	python -m pip install tensorflow-probability[tf]
	python -c "import deepxde"

	- name: Test build with PyTorch
	env:
	DDE_BACKEND: pytorch
	run: \|
	python -m pip install torch
	python -c "import deepxde"

	- name: Test build with Jax
	if: matrix.os != 'windows-latest' # jaxlib is not available on windows
	env:
	DDE_BACKEND: jax
	run: \|
	python -m pip install jax flax optax
	python -c "import deepxde"

	- name: Test build with Paddle
	env:
	DDE_BACKEND: paddle
	run: \|
	python -m pip install paddlepaddle==2.6.0 -i https://pypi.tuna.tsinghua.edu.cn/simple
	python -c "import deepxde"

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