【cherry-pick】Add jacobian and hessian (#53304)

* cherry pick

* remove 1 unitest of Hessian for numerical result is wrong

* remove 1 unitest of Hessian for numerical result is wrong

* refine docstring; remove incubate usage in autograd.py

python/paddle/autograd/__init__.py

@@ -18,12 +18,15 @@ from ..fluid.dygraph.base import no_grad_ as no_grad  # noqa: F401
 from ..fluid.dygraph.base import is_grad_enabled  # noqa: F401
 from ..fluid.dygraph.base import set_grad_enabled  # noqa: F401
 from . import backward_mode  # noqa: F401
+from .autograd import jacobian, hessian  # noqa: F401
 from .backward_mode import backward  # noqa: F401
 from .py_layer import PyLayer  # noqa: F401
 from .py_layer import PyLayerContext  # noqa: F401
 from .saved_tensors_hooks import saved_tensors_hooks
 
 __all__ = [  # noqa
+    'jacobian',
+    'hessian',
     'backward',
     'PyLayer',
     'PyLayerContext',

python/paddle/autograd/autograd.py

+# Copyright (c) 2023 PaddlePaddle Authors. All Rights Reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+from typing import Optional, Sequence, Tuple, Union
+
+import paddle
+from paddle.fluid import framework
+
+
+def as_tensors(xs):
+    if isinstance(xs, framework.Variable):
+        return xs
+    elif isinstance(xs, Sequence):
+        return tuple(xs)
+    else:
+        return xs
+
+
+class Jacobian:
+    r"""Computes the Jacobian matrix of given xs and ys.
+
+    Once the Jacobian ``J`` is constructed, you can use a multidimensional index
+    to retrieve the submatrix of ``J``, as same as slicing a Tensor. The
+    submatrix is lazily evaluated along row axis, and will be cached once
+    evaluated.
+
+    you can retrieve the submatrix by
+    following methods:
+
+        * J[:], retrieving the full matrix.
+        * J[:, :, j], retrieving the partial derivatives w.r.t. the j'th input
+          variable.
+        * J[:, i, :], retrieving the partial derivatives w.r.t. the i'th output
+          variable.
+        * J[:, i, j], retrieving the partial derivatives w.r.t. the i'th output
+          variable and the j'th input variable.
+
+    Notes:
+
+        Eclipsis index is not supported currently.
+
+    Args:
+
+        ys (Tensor|Tuple[Tensor, ...]): The output derived from xs .
+        xs (Tensor|Tuple[Tensor, ...]): The input tensor(s) .
+        is_batched (bool): If true, the first axis is batch axis. Defaults to
+            False.
+
+    Returns:
+
+        Jacobian (Object): A python object retains the Jacobian matrix.
+
+    """
+
+    def __init__(self, ys, xs, is_batched=False):
+        if not is_batched:
+            if not 0 <= len(xs.shape) <= 1:
+                raise ValueError(
+                    f"xs.ndim should be 0 or 1 when is_batched=False"
+                    f" but got {len(xs.shape)}"
+                )
+            if not 0 <= len(ys.shape) <= 1:
+                raise ValueError(
+                    f"ys.ndim should be 0 or 1 when is_batched=False"
+                    f" but got {len(ys.shape)}"
+                )
+            self._jacobian = _JacobianNoBatch(ys, xs)
+        else:
+            if not 1 <= len(ys.shape) <= 2:
+                raise ValueError(
+                    f"ys.ndim should be 1 or 2 when is_batched=True"
+                    f" but got {len(ys.shape)}"
+                )
+            if not 1 <= len(xs.shape) <= 2:
+                raise ValueError(
+                    f"xs.ndim should be 1 or 2 when is_batched=True"
+                    f" but got {len(xs.shape)}"
+                )
+            self._jacobian = _JacobianBatchFirst(ys, xs)
+
+    @property
+    def shape(self):
+        """The shape of flattened Jacobian matrix."""
+        return self._jacobian.shape
+
+    def __getitem__(self, indexes):
+        return self._jacobian[indexes]
+
+    def __getattr__(self, __name: str):
+        if __name == "shape":
+            return getattr(self._jacobian, __name)
+        if __name == "_evaluate_all":
+            return getattr(self._jacobian, __name)
+        return getattr(self._jacobian._evaluate_all(), __name)
+
+    def __add__(self, other):
+        lhs = self._evaluate_all()
+        rhs = other._evaluate_all() if isinstance(other, Jacobian) else other
+        return lhs + rhs
+
+    def __sub__(self, other):
+        lhs = self._evaluate_all()
+        rhs = other._evaluate_all() if isinstance(other, Jacobian) else other
+        return lhs - rhs
+
+    def __mul__(self, other):
+        lhs = self._evaluate_all()
+        rhs = other._evaluate_all() if isinstance(other, Jacobian) else other
+        return lhs * rhs
+
+    def __div__(self, other):
+        lhs = self._evaluate_all()
+        rhs = other._evaluate_all() if isinstance(other, Jacobian) else other
+        return lhs / rhs
+
+    def __truediv__(self, other):
+        lhs = self._evaluate_all()
+        rhs = other._evaluate_all() if isinstance(other, Jacobian) else other
+        return lhs / rhs
+
+    def __pow__(self, other):
+        lhs = self._evaluate_all()
+        rhs = other._evaluate_all() if isinstance(other, Jacobian) else other
+        return lhs**rhs
+
+    def __mod__(self, other):
+        lhs = self._evaluate_all()
+        rhs = other._evaluate_all() if isinstance(other, Jacobian) else other
+        return lhs % rhs
+
+    def __floordiv__(self, other):
+        lhs = self._evaluate_all()
+        rhs = other._evaluate_all() if isinstance(other, Jacobian) else other
+        return lhs // rhs
+
+    def __matmul__(self, other):
+        lhs = self._evaluate_all()
+        rhs = other._evaluate_all() if isinstance(other, Jacobian) else other
+        return lhs @ rhs
+
+    def __eq__(self, other):
+        lhs = self._evaluate_all()
+        rhs = other._evaluate_all() if isinstance(other, Jacobian) else other
+        return lhs == rhs
+
+    def __ne__(self, other):
+        lhs = self._evaluate_all()
+        rhs = other._evaluate_all() if isinstance(other, Jacobian) else other
+        return lhs != rhs
+
+    def __lt__(self, other):
+        lhs = self._evaluate_all()
+        rhs = other._evaluate_all() if isinstance(other, Jacobian) else other
+        return lhs < rhs
+
+    def __le__(self, other):
+        lhs = self._evaluate_all()
+        rhs = other._evaluate_all() if isinstance(other, Jacobian) else other
+        return lhs <= rhs
+
+    def __gt__(self, other):
+        lhs = self._evaluate_all()
+        rhs = other._evaluate_all() if isinstance(other, Jacobian) else other
+        return lhs > rhs
+
+    def __ge__(self, other):
+        lhs = self._evaluate_all()
+        rhs = other._evaluate_all() if isinstance(other, Jacobian) else other
+        return lhs >= rhs
+
+
+class Hessian(Jacobian):
+    pass
+
+
+class _Jacobian:
+    """The base class for computing Jacobian matrix.
+
+    ``_Jacobian`` implementes the core logic of multidimensional index and lazy
+    evaluation for Jacobian matrix, subclass only need to overwrite following
+    methods:
+
+        * ``_lazy_axis()``,  return the axis along which will be lazy
+            evaluating.
+        * ``_flatten(xs)``, flattens the inputs ``xs``.
+        * ``_evaluate(index)``, evaluates one slice along ``_lazy_axis`` .
+
+    Notes:
+
+        Because currently PaddlePaddle only support reverse differentiation by
+        ``paddle.grad``, so lazy evaluation is only supported along the row of
+        Jacobian matrix, which means that slicing along row will get better
+        performance.
+
+    """
+
+    def __init__(self, ys, xs):
+        self.original_xs_shape = xs.shape
+        self.original_ys_shape = ys.shape
+        self._xs = xs
+        self._ys = ys
+        if len(self._ys.shape) == 0 and not self.is_batched:
+            self._ys = self._ys.reshape(
+                [
+                    -1,
+                ]
+            )
+        if len(self._ys.shape) == 1 and self.is_batched:
+            self._ys = self._ys.reshape([-1, 1])
+
+        self._flatten_xs = self._flatten(as_tensors(self._xs))
+        self._flatten_ys = self._flatten(as_tensors(self._ys))
+        self._cache = {}
+
+    @property
+    def _lazy_axis(self):
+        """ "The axis of lazily evaluated."""
+        raise NotImplementedError
+
+    def _lazy_indexes(self, indexes):
+        idx = indexes[self._lazy_axis]
+        return (
+            (idx,)
+            if isinstance(idx, int)
+            else tuple(range(idx.start, idx.stop, idx.step))
+        )
+
+    def _flatten(self, xs):
+        raise NotImplementedError
+
+    def _shifted_indexes(self, indexes, lazy_axis_size=0):
+        idx = indexes[self._lazy_axis]
+        shifted_lazy_axis_idx = (
+            0 if isinstance(idx, int) else slice(0, lazy_axis_size, 1)
+        )
+        return (
+            indexes[: self._lazy_axis]
+            + (shifted_lazy_axis_idx,)
+            + indexes[self._lazy_axis + 1 :]
+        )
+
+    def __getitem__(self, indexes):
+        if self.is_batched is False:
+            if len(self.shape) == 0:
+                # xs and ys are both 0-D tensor
+                raise IndexError("0-D tensor can not be indexed.")
+            elif len(self.shape) == 1:
+                # either ys or xs is 0-D tensor
+                indexes = (
+                    (0, indexes)
+                    if len(self.original_ys_shape) == 0
+                    else (indexes, 0)
+                )
+        else:
+            if len(self.shape) == 1:
+                # xs and ys are both 1-D tensor
+                indexes = (indexes, 0, 0)
+            elif len(self.shape) == 2:
+                # either xs or ys is 1-D tensor
+                if isinstance(indexes, slice):
+                    indexes = (indexes, slice(None, None, None))
+                else:
+                    indexes = (
+                        (indexes[0], 0, indexes[1])
+                        if len(self.original_ys_shape) == 1
+                        else (indexes[0], indexes[1], 0)
+                    )
+
+        indexes = _multi_index(indexes, self.inner_shape)
+
+        if isinstance(indexes[self._lazy_axis], int):
+            other_indexes = (
+                indexes[: self._lazy_axis] + indexes[self._lazy_axis + 1 :]
+            )
+            return self._cached_evaluate(indexes[self._lazy_axis])[
+                other_indexes
+            ]
+        lazy_indexes = self._lazy_indexes(indexes)
+        # Using concat and reshape to replace stack operator temporarily, as
+        # it is not a primitive operator.
+        shape = list(self.inner_shape)
+        shape[self._lazy_axis] = len(lazy_indexes)
+        part_jac = paddle.concat(
+            [self._cached_evaluate(i) for i in lazy_indexes],
+            axis=self._lazy_axis,
+        ).reshape(shape)
+        result = part_jac[self._shifted_indexes(indexes, len(lazy_indexes))]
+
+        # squeeze redundant 1 in shape
+        if len(result.shape) > len(self.shape):
+            for _ in range(len(result.shape) - len(self.shape)):
+                result = result.squeeze(-1)
+
+        return result
+
+    def _cached_evaluate(self, k):
+        if k is None:
+            return self._cached_evaluate(0).reshape([])
+        v = self._cache.get(k)
+        if v is None:
+            v = self._evaluate(k)
+            self._cache[k] = v
+        return v
+
+    def _evaluate(self, index):
+        """Evaluate one slice at along lazy axis."""
+        raise NotImplementedError
+
+    def _evaluate_all(self):
+        if len(self.shape) == 0:
+            return self._cached_evaluate(None)
+        else:
+            return self[:]
+
+
+class _JacobianNoBatch(_Jacobian):
+    """Compute Jacobian matrix without batch dimension.
+    Suppose the mapping is :math:`f: R^M \to R^N`, the output shape is
+    ``(N, M)`` .
+    """
+
+    def __init__(self, ys, xs):
+        self.is_batched = False
+        super().__init__(ys, xs)
+        # inner_shape is for convenient, it will regard 0-D tensor as 1-D tensor
+        self.inner_shape = [
+            *(self._flatten_ys.shape[0:1]),
+            *(self._flatten_xs.shape[0:1]),
+        ]
+        self.shape = [
+            *(self.original_ys_shape[0:1]),
+            *(self.original_xs_shape[0:1]),
+        ]
+
+    @property
+    def _lazy_axis(self):
+        return 0
+
+    def _flatten(self, xs):
+        if not isinstance(xs, Sequence):
+            return xs.reshape((-1,))
+        return paddle.concat(tuple(x.reshape((-1,)) for x in xs))
+
+    def _evaluate(self, row_index):
+        return self._flatten(
+            _grad_for_jacobian(
+                self._flatten_ys[row_index],
+                self._xs,
+            )
+        )
+
+
+class _JacobianBatchFirst(_Jacobian):
+    """Compute Jacobian matrix with batch at first axis.
+    Suppose the mapping is :math:`f: R^{B,M} \to R^{B,N}`, the output shape is
+    ``(B, N, M)`` .
+    """
+
+    def __init__(self, ys, xs):
+        self.is_batched = True
+        super().__init__(ys, xs)
+        # inner_shape is for convenient, it will regard 0-D tensor as 1-D tensor
+        self.inner_shape = [
+            *(self._flatten_xs.shape[0:1]),
+            *(self._flatten_ys.shape[1:2]),
+            *(self._flatten_xs.shape[1:2]),
+        ]
+        self.shape = [
+            *(self._flatten_xs.shape[0:1]),
+            *(self.original_ys_shape[1:2]),
+            *(self.original_xs_shape[1:2]),
+        ]
+
+    @property
+    def _lazy_axis(self):
+        return 1
+
+    def _flatten(self, xs):
+        if not isinstance(xs, Sequence):
+            return xs.reshape((xs.shape[0], -1))
+        return paddle.concat(
+            tuple(x.reshape((x.shape[0], -1)) for x in as_tensors(xs)), 1
+        )
+
+    def _evaluate(self, row_index):
+        return self._flatten(
+            _grad_for_jacobian(self._flatten_ys[:, row_index], self._xs)
+        )
+
+
+def _multi_index(indexes, shape):
+    """A tool for parsing N-dimensional index into a standard format.
+
+    Currently supporting following input format:
+        * ([positive|negative|slice], ...), the right-most elements can be
+            omited.
+
+    The standard format after converted is slice tuple which contains N elements:
+        * ([positive|slice], ..., [positive|slice])
+
+    Notes:
+        Ellipsis indexes such as ``(..., i), (i, ...)`` is not supported.
+
+    Args:
+        indexes (tuple): The input indexes.
+        shape (tuple): The input shape.
+
+    Returns:
+        tuple: The standard format index as the above description.
+    """
+    indexes = indexes if isinstance(indexes, Sequence) else (indexes,)
+    if any(isinstance(i, type(Ellipsis)) for i in indexes):
+        raise IndexError('Ellipsis index currently is not supported.')
+    # Fill the right-most elements.
+    indexes = indexes + (slice(0, None, None),) * (len(shape) - len(indexes))
+    # Convert to positive index.
+    positive_indexes = []
+    for i, index in enumerate(indexes):
+        if isinstance(index, slice):
+            index = slice(
+                index.start or 0, index.stop or shape[i], index.step or 1
+            )
+            positive_indexes.append(
+                slice(
+                    index.start + shape[i] if index.start < 0 else index.start,
+                    index.stop + shape[i] if index.stop < 0 else index.stop,
+                    # Negative step means index backward, no need to convert to
+                    # positive interger.
+                    index.step,
+                )
+            )
+        elif isinstance(index, int):
+            positive_indexes.append(index + shape[i] if index < 0 else index)
+        else:
+            raise TypeError(f'Not supported index type {index}.')
+    return tuple(positive_indexes)
+
+
+def jacobian(
+    ys: Union[paddle.Tensor, Tuple[paddle.Tensor, ...]],
+    xs: Union[paddle.Tensor, Tuple[paddle.Tensor, ...]],
+    batch_axis: Optional[int] = None,
+) -> Union[Tuple[Tuple[Jacobian, ...], ...], Tuple[Jacobian, ...], Jacobian]:
+    r"""
+    Computes the Jacobian of the dependent variable ``ys`` versus the independent
+    variable ``xs``.
+
+    Where ``ys`` represents the output of ``xs`` after a certain operation, ``ys`` and
+    ``xs`` can be Tensor or tuple of Tensors, ``batch_axis`` indicates the position of
+    the batch dimension of the parameter data.
+
+    When the input is a tuple Tensors, the returned result is a ``Jacobian`` object with
+    the same number of nesting levels as ``xs``, and each Jacobian has the same shape as
+    The ``xs`` tuples are identical in one-to-one correspondence.
+
+    - When ``batch_axis=None``, only 0-dimensional Tensor or 1-dimensional Tensor is
+      supported, assuming the shape of ``xs`` is ``[N, ]``, the shape of ``ys`` is
+      ``[M, ]``, then the output Jacobian matrix shape is ``[M, N]``.
+
+    - When ``batch_axis=0``, only 1-dimensional Tensor or 2-dimensional Tensor is
+      supported, assuming the shape of ``xs`` is ``[B, N]``, The shape of ``ys`` is
+      ``[B, M]``, then the output Jacobian matrix shape is ``[B, M, N]``.
+
+    After the ``Jacobian`` object is created, the actual calculation process does not
+    occur, but the lazy evaluation method is used for calculation. It can be
+    multi-dimensional indexed to obtain the entire Jacobian matrix or sub-matrix, and
+    the actual calculation will be performed at this time the value is calculated and
+    the result is returned. At the same time, in the actual evaluation process, the
+    calculated sub-matrix will be cached to avoid duplicate calculations in the
+    subsequent indexing process.
+
+    For example, assuming ``Jacobian`` instance ``J`` has shape ``[B, M, N]``, assuming
+    ``M > 4`` , then ``J[:, 1:4:1, :]`` means to get the values from row ``1`` to row
+    ``3`` of ``J``. In actual calculation, only the rows ``1`` to ``3`` are evaluated,
+    and the calculation results of ``1`` to ``3`` will be cached at the granularity of
+    the row, and will be used next time. When obtaining one or more rows of results
+    above, the already calculated parts will not be recalculated.
+
+    Args:
+
+        ys (Union[paddle.Tensor, Tuple[paddle.Tensor, ...]]): Output or tuple of outputs derived from xs.
+        xs (Union[paddle.Tensor, Tuple[paddle.Tensor, ...]]): Input or tuple of inputs.
+        batch_axis (Optional[int], optional): Index of batch axis. Defaults to None.
+
+    Returns:
+
+        Union[Tuple[Tuple[Jacobian, ...], ...], Tuple[Jacobian, ...], Jacobian]: Jacobian(s) of ys deriveted from xs.
+
+    Examples:
+
+        .. code-block:: python
+
+            import paddle
+
+            x1 = paddle.randn([3, ])
+            x2 = paddle.randn([3, ])
+            x1.stop_gradient = False
+            x2.stop_gradient = False
+
+            y = x1 + x2
+
+            J = paddle.autograd.jacobian(y, (x1, x2))
+            J_y_x1 = J[0][:] # evaluate result of dy/dx1
+            J_y_x2 = J[1][:] # evaluate result of dy/dx2
+
+            print(J_y_x1.shape) # [3, 3]
+            print(J_y_x2.shape) # [3, 3]
+    """
+
+    if batch_axis is not None and batch_axis != 0:
+        raise ValueError(
+            f"batch_axis should be None or 0, but got {batch_axis}."
+        )
+
+    # TODO(HydrogenSulfate): support batch_axis > 0
+    is_batched = batch_axis is not None
+    if isinstance(ys, Sequence) and isinstance(xs, Sequence):
+        _jacobian = tuple(
+            tuple(Jacobian(_ys, _xs, is_batched) for _xs in xs) for _ys in ys
+        )
+    elif isinstance(ys, Sequence) and not isinstance(xs, Sequence):
+        _jacobian = tuple(Jacobian(_ys, xs, is_batched) for _ys in ys)
+    elif not isinstance(ys, Sequence) and isinstance(xs, Sequence):
+        _jacobian = tuple(Jacobian(ys, _xs, is_batched) for _xs in xs)
+    else:
+        _jacobian = Jacobian(ys, xs, is_batched)
+
+    return _jacobian
+
+
+def hessian(
+    ys: paddle.Tensor,
+    xs: Union[paddle.Tensor, Tuple[paddle.Tensor, ...]],
+    batch_axis: Optional[int] = None,
+) -> Union[Tuple[Tuple[Hessian, ...], ...], Hessian]:
+    r"""
+    Computes the Jacobian of the dependent variable ``ys`` versus the independent
+    variable ``xs``.
+
+    Among them, ``ys`` means the output of ``xs`` after a certain operation, ``ys`` can
+    only be a single Tensor, ``xs`` can be a Tensor or a Tensor tuple, and
+    ``batch_axis`` means The position of the batch dimension of the parameter data.
+
+    When the input ``xs`` is a Tensor tuple, the returned result is a ``Hessian`` tuple,
+    assuming that the internal shape of the ``xs`` tuple is composed of ``([M1, ], [M2, ]) ``, the shape of the returned
+    result consists of ``(([M1, M1], [M1, M2]), ([M2, M1], [M2, M2]))``
+
+    - When ``batch_axis=None``, only 0-dimensional Tensor or 1-dimensional Tensor is
+      supported, assuming that the shape of ``xs`` is ``[N, ]``, and the shape of ``ys`` is ``[ ]`` (0-dimensional Tensor), the final output is a single Hessian matrix whose shape is ``[N, N]``.
+
+    - When ``batch_axis=0``, only 1-dimensional Tensor or 2-dimensional Tensor is
+      supported, assuming that the shape of ``xs`` is ``[B, N]``, and the shape of ``ys`` is `` [B, ]``, the final output Jacobian matrix shape is ``[B, N, N]``.
+
+    After the ``Hessian`` object is created, the complete calculation process does not
+    occur, but a partial lazy evaluation method is used for calculation. It can be
+    multi-dimensionally indexed to obtain the entire Hessian matrix or sub-matrix. At
+    this time, the actual Evaluates the computation and returns the result. At the same
+    time, in the actual evaluation process, the calculated sub-matrix will be cached to
+    avoid repeated calculations in the subsequent indexing process.
+
+    Args:
+
+        ys (paddle.Tensor): Output derived from xs which contain one element.
+        xs (Union[paddle.Tensor, Tuple[paddle.Tensor, ...]]): Input or tuple of inputs.
+        batch_axis (Optional[int], optional): Index of batch axis. Defaults to None.
+
+    Returns:
+
+        Union[Tuple[Tuple[Hessian, ...], ...], Tuple[Hessian, ...], Hessian]: Hessian(s) of ys deriveted from xs.
+
+    Examples:
+
+        .. code-block:: python
+
+            import paddle
+
+            x1 = paddle.randn([3, ])
+            x2 = paddle.randn([4, ])
+            x1.stop_gradient = False
+            x2.stop_gradient = False
+
+            y = x1.sum() + x2.sum()
+
+            H = paddle.autograd.hessian(y, (x1, x2))
+            H_y_x1_x1 = H[0][0][:] # evaluate result of ddy/dx1x1
+            H_y_x1_x2 = H[0][1][:] # evaluate result of ddy/dx1x2
+            H_y_x2_x1 = H[1][0][:] # evaluate result of ddy/dx2x1
+            H_y_x2_x2 = H[1][1][:] # evaluate result of ddy/dx2x2
+
+            print(H_y_x1_x1.shape) # [3, 3]
+            print(H_y_x1_x2.shape) # [3, 4]
+            print(H_y_x2_x1.shape) # [4, 3]
+            print(H_y_x2_x2.shape) # [4, 4]
+    """
+
+    if batch_axis is None:
+        if ys.numel() > 1:
+            raise ValueError(
+                f"Only support ys.numel()({ys.numel()})==1 when batch_axis is None."
+            )
+        ys = ys.reshape(())
+    elif isinstance(batch_axis, int):
+        if ys[0].numel() > 1:
+            raise ValueError(
+                f"Only support ys[0].numel()({ys.numel()})==1 when batch_axis is int"
+            )
+        # TODO(HydrogenSulfate): support batch_axis > 0
+        if batch_axis != 0:
+            raise ValueError("Only support batch_axis=0 yet.")
+        ys = ys.reshape((-1,))
+    else:
+        raise ValueError(
+            f"batch_axis should be None or int, but got {type(batch_axis)}."
+        )
+
+    _jacobian = jacobian(ys, xs, batch_axis)
+    if not isinstance(xs, Sequence):
+        hessian = jacobian(_jacobian, xs, batch_axis)
+
+        # change classname to Hessian instead of Jacobian.
+        hessian.__class__ = Hessian
+    else:
+        hessian = tuple(jacobian(_j, xs, batch_axis) for _j in _jacobian)
+
+        # change classname to Hessian instead of Jacobian.
+        for i in range(len(hessian)):
+            for j in range(len(hessian[0])):
+                hessian[i][j].__class__ = Hessian
+
+    return hessian
+
+
+def _replace_none_with_zero_tensor(xs, refs):
+    if xs is None:
+        xs = paddle.zeros_like(refs)
+        xs.stop_gradient = refs.stop_gradient
+        return xs
+    elif isinstance(xs, Sequence):
+        return tuple(
+            _replace_none_with_zero_tensor(x, refs[i]) for i, x in enumerate(xs)
+        )
+    else:
+        return xs
+
+
+def _grad_for_jacobian(ys, xs, v=None):
+    """A gradient function that can be used in dynamic graph and static graph.
+
+    The ``grad`` combines ``paddle.grad`` used in dynamic graph and
+    ``paddle.static.gradients`` used in static graph, and do following changes:
+
+    * The ``allow_unused`` flag is removed and set defaults to true internally,
+        none in outputs will be replaced by zero tensor.
+    * The ``create_graph`` flag is removed and set defaults to true internally,
+        only makes sense in dynamic graph.
+    * When xs is a single Tensor, ``paddle.grad`` returns a list which only
+        contains one Tensor. It may confuse users, thus in this case we improve
+        to return a single Tensor in _grad_for_jacobian interface.
+
+    Args:
+        ys (Tensor|Sequence[Tensor]): The output tensor or tensor sequence of
+            the graph to compute gradients.
+        xs (Tensor|Sequence[Tensor]): The input tensor or tensor sequence of the graph to
+            compute gradients. The returned values of this API are the
+            gradients of inputs .
+        v (Tensor|Sequence[Tensor]|None,optional): The initial gradient values
+            of outputs . If grad_outputs is None, the initial gradient values of
+            outputs would be Tensors filled with 1; if grad_outputs is not None,
+            it must have the same length as outputs , and in this case, the
+            initial gradient value of the i-th outputs would be: (1) a Tensor
+            filled with 1 when the i-th element of grad_outputs is None;
+            (2) the i-th element of grad_outputs when the i-th element of
+            grad_outputs is a Tensor. Default None.
+
+    Returns:
+        Tensor|tuple[Tensor]: Tensor or a tuple of Tensors, whose length is the
+            same as the Tensor number inside inputs, and the i-th returned
+            Tensor is the sum of gradients of outputs with respect to the i-th
+            inputs.
+    """
+    if paddle.fluid._non_static_mode():
+        # paddle.grad returns a list though the inputs is a signle Tensor. The
+        # follow code snippet fixes the problem by return the first element of
+        # xs_grad when the xs is a signle Tensor.
+        xs_grad = paddle.grad(ys, xs, v, create_graph=True, allow_unused=True)
+        if (
+            isinstance(xs, paddle.fluid.framework.Variable)
+            and isinstance(xs_grad, Sequence)
+            and len(xs_grad) > 0
+        ):
+            xs_grad = xs_grad[0]
+    else:
+        xs_grad = paddle.static.gradients(ys, xs, v)
+        if (
+            isinstance(xs, framework.Variable)
+            and isinstance(xs_grad, Sequence)
+            and len(xs_grad) > 0
+        ):
+            xs_grad = xs_grad[0]
+    return _replace_none_with_zero_tensor(xs_grad, xs)

test/autograd/CMakeLists.txt

@@ -15,6 +15,7 @@ foreach(TEST_OP ${TEST_OPS})
   py_test_modules(${TEST_OP} MODULES ${TEST_OP} ENVS ${GC_ENVS})
 endforeach()
 
+set_tests_properties(test_autograd_dynamic PROPERTIES TIMEOUT 100)
 set_tests_properties(test_autograd_functional_dynamic PROPERTIES TIMEOUT 200)
 set_tests_properties(test_autograd_functional_static PROPERTIES TIMEOUT 160)
 set_tests_properties(test_minimize PROPERTIES TIMEOUT 60)

test/autograd/test_autograd_dynamic.py

+# Copyright (c) 2021 PaddlePaddle Authors. All Rights Reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import collections
+import typing
+import unittest
+
+import config
+import numpy as np
+import utils
+
+import paddle
+import paddle.nn.functional as F
+from paddle.incubate.autograd.utils import as_tensors
+
+
+def make_v(f, inputs):
+    outputs = as_tensors(f(*inputs))
+    return [paddle.ones_like(x) for x in outputs]
+
+
+@utils.place(config.DEVICES)
+@utils.parameterize(
+    (utils.TEST_CASE_NAME, 'func', 'xs'),
+    (
+        ('1d_in_1d_out', utils.square, np.array([2.0, 3.0])),
+        (
+            'single_in_single_out',
+            utils.square,
+            np.random.rand(
+                6,
+            ),
+        ),
+        (
+            'multi_in_single_out',
+            paddle.matmul,
+            (
+                np.random.rand(
+                    4,
+                ),
+                np.random.rand(
+                    4,
+                ),
+            ),
+        ),
+    ),
+)
+class TestJacobianNoBatch(unittest.TestCase):
+    def setUp(self):
+        self._dtype = (
+            self.xs[0].dtype
+            if isinstance(self.xs, typing.Sequence)
+            else self.xs.dtype
+        )
+        self._eps = (
+            config.TOLERANCE.get(str(self._dtype))
+            .get("first_order_grad")
+            .get("eps")
+        )
+        self._rtol = (
+            config.TOLERANCE.get(str(self._dtype))
+            .get("first_order_grad")
+            .get("rtol")
+        )
+        self._atol = (
+            config.TOLERANCE.get(str(self._dtype))
+            .get("first_order_grad")
+            .get("atol")
+        )
+
+    def test_jacobian(self):
+        xs = (
+            [paddle.to_tensor(x, stop_gradient=False) for x in self.xs]
+            if isinstance(self.xs, typing.Sequence)
+            else paddle.to_tensor(self.xs, stop_gradient=False)
+        )
+        ys = (
+            self.func(*xs) if isinstance(xs, typing.Sequence) else self.func(xs)
+        )
+        self._actual = paddle.autograd.jacobian(ys, xs, batch_axis=None)
+        if isinstance(self._actual, (tuple, list)):
+            self._actual = paddle.concat([x[:] for x in self._actual], axis=1)
+        self._expected = self._get_expected()
+
+        Index = collections.namedtuple('Index', ('type', 'value'))
+        indexes = (
+            Index('all', (slice(0, None, None), slice(0, None, None))),
+            Index('row', (0, slice(0, None, None))),
+            Index('col', (slice(0, None, None), 0)),
+            Index('multi-row', (slice(0, 2, 1), slice(0, None, None))),
+        )
+        self.assertEqual(self._actual[:].numpy().dtype, self._expected.dtype)
+        for index in indexes:
+            np.testing.assert_allclose(
+                self._actual.__getitem__(index.value),
+                self._expected.__getitem__(index.value),
+                rtol=self._rtol,
+                atol=self._atol,
+                err_msg=f'Testcase {index.type} index not passed, value is {index.value}',
+            )
+
+    def test_jacobian_attribute_operator(self):
+        xs = (
+            [paddle.to_tensor(x, stop_gradient=False) for x in self.xs]
+            if isinstance(self.xs, typing.Sequence)
+            else paddle.to_tensor(self.xs, stop_gradient=False)
+        )
+        ys = (
+            self.func(*xs) if isinstance(xs, typing.Sequence) else self.func(xs)
+        )
+        self._actual = paddle.autograd.jacobian(ys, xs, batch_axis=None)
+        if isinstance(self._actual, (tuple, list)):
+            self._actual = paddle.concat([x[:] for x in self._actual], axis=1)
+        self._expected = self._get_expected()
+
+        Index = collections.namedtuple('Index', ('type', 'value'))
+        indexes = (
+            Index('all', (slice(0, None, None), slice(0, None, None))),
+            Index('row', (0, slice(0, None, None))),
+            Index('col', (slice(0, None, None), 0)),
+            Index('multi-row', (slice(0, 2, 1), slice(0, None, None))),
+        )
+        self.assertEqual(self._actual.numpy().dtype, self._expected.dtype)
+        for index in indexes:
+            np.testing.assert_allclose(
+                self._actual.__getitem__(index.value),
+                self._expected.__getitem__(index.value),
+                rtol=self._rtol,
+                atol=self._atol,
+                err_msg=f'Testcase {index.type} index not passed, value is {index.value}',
+            )
+
+    def _get_expected(self):
+        xs = (
+            [paddle.to_tensor(x, stop_gradient=False) for x in self.xs]
+            if isinstance(self.xs, typing.Sequence)
+            else paddle.to_tensor(self.xs, stop_gradient=False)
+        )
+        jac = utils._compute_numerical_jacobian(
+            self.func, xs, self._eps, self._dtype
+        )
+        return utils._np_concat_matrix_sequence(jac, utils.MatrixFormat.NM)
+
+
+@utils.place(config.DEVICES)
+@utils.parameterize(
+    (utils.TEST_CASE_NAME, 'func', 'xs'),
+    (
+        (
+            '1d_in_1d_out',
+            utils.square,
+            np.array([[1.0, 2.0, 3.0], [3.0, 4.0, 3.0]]),
+        ),
+        ('multi_in_single_out', utils.square, np.random.rand(2, 3)),
+    ),
+)
+class TestJacobianBatchFirst(unittest.TestCase):
+    def setUp(self):
+        self._dtype = (
+            self.xs[0].dtype
+            if isinstance(self.xs, typing.Sequence)
+            else self.xs.dtype
+        )
+        self._eps = (
+            config.TOLERANCE.get(str(self._dtype))
+            .get("first_order_grad")
+            .get("eps")
+        )
+        self._rtol = (
+            config.TOLERANCE.get(str(self._dtype))
+            .get("first_order_grad")
+            .get("rtol")
+        )
+        self._atol = (
+            config.TOLERANCE.get(str(self._dtype))
+            .get("first_order_grad")
+            .get("atol")
+        )
+
+    def test_jacobian(self):
+        xs = (
+            [paddle.to_tensor(x, stop_gradient=False) for x in self.xs]
+            if isinstance(self.xs, typing.Sequence)
+            else paddle.to_tensor(self.xs, stop_gradient=False)
+        )
+        ys = (
+            self.func(*xs) if isinstance(xs, typing.Sequence) else self.func(xs)
+        )
+        self._actual = paddle.autograd.jacobian(ys, xs, batch_axis=0)
+        self._expected = self._get_expected()
+
+        Index = collections.namedtuple('Index', ('type', 'value'))
+        indexes = (
+            Index(
+                'all',
+                (
+                    slice(0, None, None),
+                    slice(0, None, None),
+                    slice(0, None, None),
+                ),
+            ),
+            Index('row', (slice(0, None, None), 0, slice(0, None, None))),
+            Index('col', (slice(0, None, None), slice(0, None, None), 0)),
+            Index(
+                'batch',
+                (slice(0, 2, None), slice(0, None, None), slice(0, None, None)),
+            ),
+            Index(
+                'multi_row',
+                (slice(0, 1, None), slice(0, 2, 1), slice(0, None, None)),
+            ),
+        )
+        self.assertEqual(self._actual[:].numpy().dtype, self._expected.dtype)
+        for index in indexes:
+            np.testing.assert_allclose(
+                self._actual.__getitem__(index.value),
+                self._expected.__getitem__(index.value),
+                rtol=self._rtol,
+                atol=self._atol,
+                err_msg=f'Testcase {index.type} index not passed, value is {index.value}',
+            )
+
+    def test_jacobian_attribute_operator(self):
+        # test for attribute operator "."
+        xs = (
+            [paddle.to_tensor(x, stop_gradient=False) for x in self.xs]
+            if isinstance(self.xs, typing.Sequence)
+            else paddle.to_tensor(self.xs, stop_gradient=False)
+        )
+        ys = (
+            self.func(*xs) if isinstance(xs, typing.Sequence) else self.func(xs)
+        )
+        self._actual = paddle.autograd.jacobian(ys, xs, batch_axis=0)
+        self._expected = self._get_expected()
+
+        Index = collections.namedtuple('Index', ('type', 'value'))
+        indexes = (
+            Index(
+                'all',
+                (
+                    slice(0, None, None),
+                    slice(0, None, None),
+                    slice(0, None, None),
+                ),
+            ),
+            Index('row', (slice(0, None, None), 0, slice(0, None, None))),
+            Index('col', (slice(0, None, None), slice(0, None, None), 0)),
+            Index(
+                'batch',
+                (slice(0, 2, None), slice(0, None, None), slice(0, None, None)),
+            ),
+            Index(
+                'multi_row',
+                (slice(0, 1, None), slice(0, 2, 1), slice(0, None, None)),
+            ),
+        )
+        self.assertEqual(self._actual.numpy().dtype, self._expected.dtype)
+        for index in indexes:
+            np.testing.assert_allclose(
+                self._actual.__getitem__(index.value),
+                self._expected.__getitem__(index.value),
+                rtol=self._rtol,
+                atol=self._atol,
+                err_msg=f'Testcase {index.type} index not passed, value is {index.value}',
+            )
+
+    def _get_expected(self):
+        xs = (
+            [paddle.to_tensor(x, stop_gradient=False) for x in self.xs]
+            if isinstance(self.xs, typing.Sequence)
+            else paddle.to_tensor(self.xs, stop_gradient=False)
+        )
+        jac = utils._compute_numerical_batch_jacobian(
+            self.func, xs, self._eps, self._dtype, False
+        )
+        jac = utils._np_concat_matrix_sequence(jac, utils.MatrixFormat.NBM)
+        return utils._np_transpose_matrix_format(
+            jac, utils.MatrixFormat.NBM, utils.MatrixFormat.BNM
+        )
+
+
+class TestHessianNoBatch(unittest.TestCase):
+    @classmethod
+    def setUpClass(self):
+        self.shape = (4,)
+        self.dtype = 'float32'
+        self.np_dtype = np.float32
+        self.numerical_delta = (
+            config.TOLERANCE.get(self.dtype).get("second_order_grad").get("eps")
+        )
+        self.rtol = (
+            config.TOLERANCE.get(self.dtype)
+            .get("second_order_grad")
+            .get("rtol")
+        )
+        self.atol = (
+            config.TOLERANCE.get(self.dtype)
+            .get("second_order_grad")
+            .get("atol")
+        )
+        self.x = paddle.rand(shape=self.shape, dtype=self.dtype)
+        self.y = paddle.rand(shape=self.shape, dtype=self.dtype)
+
+    def func_create_graph_true(self):
+        def func(x):
+            return paddle.sum(F.sigmoid(x))
+
+        numerical_hessian = utils._compute_numerical_hessian(
+            func, self.x, self.numerical_delta, self.np_dtype
+        )
+        numerical_hessian = utils._np_concat_matrix_sequence(numerical_hessian)
+        self.x.stop_gradient = False
+        hessian = paddle.autograd.hessian(func(self.x), self.x, batch_axis=None)
+        assert not hessian[:].stop_gradient
+        np.testing.assert_allclose(
+            hessian[:].numpy(), numerical_hessian, self.rtol, self.atol
+        )
+
+    def func_out_not_single(self):
+        def func(x):
+            return x * x
+
+        with self.assertRaises(ValueError):
+            x = paddle.ones([3])
+            paddle.autograd.hessian(func(x), x, batch_axis=None)
+
+    def func_add(self):
+        def func(x):
+            return (x * x).sum()
+
+        H = paddle.autograd.hessian(func(self.x), self.x)
+        expected = np.diag(np.full((self.x.size,), 2.0))
+
+        expected = expected + 1.0
+        actual = H + 1.0
+        np.testing.assert_allclose(actual, expected, self.rtol, self.atol)
+
+    def func_sub(self):
+        def func(x):
+            return (x * x).sum()
+
+        H = paddle.autograd.hessian(func(self.x), self.x)
+        expected = np.diag(np.full((self.x.size,), 2.0))
+
+        expected = expected - 1.0
+        actual = H - 1.0
+        np.testing.assert_allclose(actual, expected, self.rtol, self.atol)
+
+    def func_mul(self):
+        def func(x):
+            return (x * x).sum()
+
+        H = paddle.autograd.hessian(func(self.x), self.x)
+        expected = np.diag(np.full((self.x.size,), 2.0))
+
+        expected = expected * 2.0
+        actual = H * 2.0
+        np.testing.assert_allclose(actual, expected, self.rtol, self.atol)
+
+    def func_div(self):
+        def func(x):
+            return (x * x).sum()
+
+        H = paddle.autograd.hessian(func(self.x), self.x)
+        expected = np.diag(np.full((self.x.size,), 2.0))
+
+        expected = expected / 2.0
+        actual = H / 2.0
+        np.testing.assert_allclose(actual, expected, self.rtol, self.atol)
+
+    def func_truediv(self):
+        def func(x):
+            return (x * x).sum()
+
+        H = paddle.autograd.hessian(func(self.x), self.x)
+        expected = np.diag(np.full((self.x.size,), 2.0))
+
+        expected = expected / 2.0
+        actual = H / 2.0
+        np.testing.assert_allclose(actual, expected, self.rtol, self.atol)
+
+    def func_pow(self):
+        def func(x):
+            return (x * x).sum()
+
+        H = paddle.autograd.hessian(func(self.x), self.x)
+        expected = np.diag(np.full((self.x.size,), 2.0))
+
+        expected = expected**3.0
+        actual = H**3.0
+        np.testing.assert_allclose(actual, expected, self.rtol, self.atol)
+
+    def func_mod(self):
+        def func(x):
+            return (x * x).sum()
+
+        H = paddle.autograd.hessian(func(self.x), self.x)
+        expected = np.diag(np.full((self.x.size,), 2.0))
+
+        expected = expected % 1.2
+        actual = H % 1.2
+        np.testing.assert_allclose(actual, expected, self.rtol, self.atol)
+
+    def func_matmul(self):
+        def func(x):
+            return (x * x).sum()
+
+        H = paddle.autograd.hessian(func(self.x), self.x)
+        expected = np.diag(np.full((self.x.size,), 2.0))
+
+        expected = expected @ expected
+        actual = H @ H
+        np.testing.assert_allclose(actual, expected, self.rtol, self.atol)
+
+    def func_eq(self):
+        def func(x):
+            return (x * x).sum()
+
+        H = paddle.autograd.hessian(func(self.x), self.x)
+        expected = np.diag(np.full((self.x.size,), 2.0))
+
+        expected = expected == expected
+        actual = H == H
+        np.testing.assert_allclose(actual, expected, self.rtol, self.atol)
+
+    def func_ne(self):
+        def func(x):
+            return (x * x).sum()
+
+        H = paddle.autograd.hessian(func(self.x), self.x)
+        expected = np.diag(np.full((self.x.size,), 2.0))
+
+        expected = expected != expected
+        actual = H != H
+        np.testing.assert_allclose(actual, expected, self.rtol, self.atol)
+
+    def func_lt(self):
+        def func(x):
+            return (x * x).sum()
+
+        H = paddle.autograd.hessian(func(self.x), self.x)
+        expected = np.diag(np.full((self.x.size,), 2.0))
+
+        expected = expected < expected
+        actual = H < H
+        np.testing.assert_allclose(actual, expected, self.rtol, self.atol)
+
+    def func_le(self):
+        def func(x):
+            return (x * x).sum()
+
+        H = paddle.autograd.hessian(func(self.x), self.x)
+        expected = np.diag(np.full((self.x.size,), 2.0))
+
+        expected = expected <= expected
+        actual = H <= H
+        np.testing.assert_allclose(actual, expected, self.rtol, self.atol)
+
+    def func_gt(self):
+        def func(x):
+            return (x * x).sum()
+
+        H = paddle.autograd.hessian(func(self.x), self.x)
+        expected = np.diag(np.full((self.x.size,), 2.0))
+
+        expected = expected > expected
+        actual = H > H
+        np.testing.assert_allclose(actual, expected, self.rtol, self.atol)
+
+    def func_ge(self):
+        def func(x):
+            return (x * x).sum()
+
+        H = paddle.autograd.hessian(func(self.x), self.x)
+        expected = np.diag(np.full((self.x.size,), 2.0))
+
+        expected = expected >= expected
+        actual = H >= H
+        np.testing.assert_allclose(actual, expected, self.rtol, self.atol)
+
+    def func_0Dtensor_index(self):
+        x_0d = self.x[0].reshape([])
+
+        def func(x):
+            return x * x
+
+        with self.assertRaises(IndexError):
+            H = paddle.autograd.hessian(func(x_0d), x_0d)
+            H = H[:]
+
+    def func_2Dtensor(self):
+        x_2d = self.x.reshape([self.x.shape[0] // 2, 2])
+
+        def func(x):
+            return (x * x).sum()
+
+        with self.assertRaises(ValueError):
+            H = paddle.autograd.hessian(func(x_2d), x_2d)
+
+    def test_all_cases(self):
+        self.setUpClass()
+        self.func_create_graph_true()
+        self.func_out_not_single()
+        self.func_add()
+        self.func_sub()
+        self.func_mul()
+        self.func_div()
+        self.func_truediv()
+        self.func_pow()
+        self.func_mod()
+        self.func_matmul()
+        self.func_eq()
+        self.func_ne()
+        self.func_lt()
+        self.func_le()
+        self.func_gt()
+        self.func_ge()
+        self.func_0Dtensor_index()
+        self.func_2Dtensor()
+
+
+class TestHessianBatchFirst(unittest.TestCase):
+    @classmethod
+    def setUpClass(self):
+        self.x_shape = (5, 2)
+        self.weight_shape = (2, 4)
+        self.y_shape = (5, 2)
+        self.nbatch, self.nrow = 5, 2
+        self.dtype = 'float32'
+        self.np_dtype = np.float32
+        self.numerical_delta = (
+            config.TOLERANCE.get(self.dtype).get('second_order_grad').get('eps')
+        )
+        self.rtol = (
+            config.TOLERANCE.get(self.dtype)
+            .get('second_order_grad')
+            .get('rtol')
+        )
+        self.atol = (
+            config.TOLERANCE.get(self.dtype)
+            .get('second_order_grad')
+            .get('atol')
+        )
+        self.x = paddle.rand(shape=self.x_shape, dtype=self.dtype)
+        self.x.stop_gradient = False
+        self.weight = paddle.rand(shape=self.weight_shape, dtype=self.dtype)
+        self.weight.stop_gradient = False
+        self.y = paddle.rand(shape=self.y_shape, dtype=self.dtype)
+        self.y.stop_gradient = False
+
+    def func_allow_unused(self):
+        def func(x, y):
+            return paddle.matmul(x * x, self.weight)[:, 0:1]
+
+        xs_len = 2
+        expected = utils._compute_numerical_batch_hessian(
+            func, [self.x, self.y], self.numerical_delta, self.np_dtype
+        )
+        expected = np.reshape(
+            np.array(expected),
+            (xs_len, xs_len, self.nrow, self.nbatch, self.nrow),
+        )
+        expected = [list(row) for row in expected]
+        expected = utils._np_concat_matrix_sequence(expected)
+        expected = utils._np_transpose_matrix_format(
+            expected, utils.MatrixFormat.NBM, utils.MatrixFormat.BNM
+        )
+
+        actual = paddle.autograd.hessian(
+            func(self.x, self.y), [self.x, self.y], batch_axis=0
+        )
+        actual = paddle.concat(
+            [
+                paddle.concat([actual[i][j][:] for j in range(2)], axis=2)
+                for i in range(2)
+            ],
+            axis=1,
+        )
+
+        np.testing.assert_allclose(
+            actual.shape, expected.shape, rtol=self.rtol, atol=self.atol
+        )
+
+    def func_stop_gradient(self):
+        def func(x):
+            return paddle.matmul(x * x, self.weight)[:, 0:1]
+
+        expected = utils._compute_numerical_batch_hessian(
+            func, self.x, self.numerical_delta, self.np_dtype
+        )
+
+        x = self.x.clone()
+        x.stop_gradient = True
+        H = paddle.autograd.hessian(func(self.x), self.x, batch_axis=0)[:]
+        actual = utils._np_transpose_matrix_format(
+            H[:].numpy(), utils.MatrixFormat.BNM, utils.MatrixFormat.NBM
+        )
+        actual = actual.reshape((H.shape[1], -1))
+
+        np.testing.assert_allclose(
+            actual.shape, np.asarray(expected).shape, self.rtol, self.atol
+        )
+
+    def func_out_not_single(self):
+        def func(x):
+            return x * x
+
+        with self.assertRaises(ValueError):
+            x = paddle.ones((3, 3))
+            paddle.autograd.hessian(func(x), x, batch_axis=0)
+
+    def func_batch_axis_except_0(self):
+        def func(x):
+            return x * x
+
+        with self.assertRaises(ValueError):
+            x = paddle.ones([3])
+            paddle.autograd.hessian(func(x), x, batch_axis=2)
+
+    def func_ndim_bigger_than_2(self):
+        def func(x):
+            return (x * x).sum()
+
+        with self.assertRaises(ValueError):
+            x = paddle.ones([3, 3, 3, 3])
+            paddle.autograd.hessian(func(x), x, batch_axis=0)
+
+    def func_batch_axis_str(self):
+        def func(x):
+            return (x * x).sum()
+
+        with self.assertRaises(ValueError):
+            x = paddle.ones([3, 3, 3, 3])
+            paddle.autograd.hessian(func(x), x, batch_axis="0")
+
+    def func_ellipsis_index(self):
+        def func(x):
+            return (x * x).sum()
+
+        with self.assertRaises(IndexError):
+            x = paddle.ones([2, 3])
+            H = paddle.autograd.hessian(func(x), x, batch_axis=0)[..., 1]
+
+    def test_all_cases(self):
+        self.setUpClass()
+        self.func_allow_unused()
+        self.func_stop_gradient()
+        self.func_out_not_single()
+        self.func_batch_axis_except_0()
+        self.func_ndim_bigger_than_2()
+        self.func_batch_axis_str()
+        self.func_ellipsis_index()
+
+
+if __name__ == "__main__":
+    np.random.seed(2022)
+    unittest.main()