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- mindspore.nn.Adam
- ==================
-
- .. py:class:: mindspore.nn.Adam(*args, **kwargs)
-
- ͨAdaptive Moment Estimation (Adam)㷨ݶȡ
-
- `Adam: A Method for Stochastic Optimization <https://arxiv.org/abs/1412.6980>`_
-
- ʽ£
-
- .. math::
- \begin{array}{ll} \\
- m_{t+1} = \beta_1 * m_{t} + (1 - \beta_1) * g \\
- v_{t+1} = \beta_2 * v_{t} + (1 - \beta_2) * g * g \\
- l = \alpha * \frac{\sqrt{1-\beta_2^t}}{1-\beta_1^t} \\
- w_{t+1} = w_{t} - l * \frac{m_{t+1}}{\sqrt{v_{t+1}} + \epsilon}
- \end{array}
-
- :math:`m` һ `moment1` :math:`v` ڶ `moment2` :math:`g` `gradients` :math:`l` ӣ:math:`\beta_1,\beta_2` `beta1` `beta2` :math:`t` ²裬:math:`beta_1^t` :math:`beta_2^t` `beta1_power` `beta2_power` :math:`\alpha` `learning_rate` :math:`w` `params` :math:`\epsilon` `eps`
-
- .. note::
- ǰʹSparseGatherV2ӣŻִϡ㣬ͨ `target` ΪCPUhostϽϡ㡣
- ϡڳС
-
- ڲδʱŻõ `weight_decay` Ӧƺ"beta""gamma"ͨɵȨ˥ԡʱÿ `weight_decay` δãʹŻõ `weight_decay`
-
-
- ****
-
- - **params** (Union[list[Parameter], list[dict]]) - `Parameter` ɵбֵɵббԪֵʱֵļ"params""lr""weight_decay""grad_centralization""order_params"
-
- - **params** - ǰȨأֵ `Parameter` б
- - **lr** - ѡд"lr"ʹöӦֵΪѧϰʡûУʹŻõ `learning_rate` Ϊѧϰʡ
- - **weight_decay** - ѡд"weight_decayʹöӦֵΪȨ˥ֵûУʹŻõ `weight_decay` ΪȨ˥ֵ
- - **grad_centralization** - ѡд"grad_centralization"ʹöӦֵֵΪ͡ûУΪ `grad_centralization` ΪFalseòھ㡣
- - **order_params** - ѡӦֵԤڵIJ˳ʹò鹦ʱͨʹø `parameters` ˳ܡд"order_params"Ըе"order_params"еIJijһ `params` С
-
- - **learning_rate (Union[float, Tensor, Iterable, LearningRateSchedule]): Ĭֵ1e-3
-
- - **float** - ̶ѧϰʡڵ㡣
- - **int** - ̶ѧϰʡڵ㡣ͻᱻתΪ
- - **Tensor** - DZһάǹ̶ѧϰʡһάǶ̬ѧϰʣiȡеiֵΪѧϰʡ
- - **Iterable** - ̬ѧϰʡiȡiֵΪѧϰʡ
- - **LearningRateSchedule** - ̬ѧϰʡѵУŻʹòstepΪ룬 `LearningRateSchedule` ʵ㵱ǰѧϰʡ
-
- - **beta1** (float) - `moment1` ָ˥ʡΧ0.0,1.0Ĭֵ0.9
- - **beta2** (float) - `moment2` ָ˥ʡΧ0.0,1.0Ĭֵ0.999
- - **eps** (float) - ӵĸУֵȶԡ0Ĭֵ1e-8
- - **use_locking** (bool) - ǷԲ¼ΪTrue `w` `m` `v` tensor½ܵıΪFalseԤ⡣ĬֵFalse
- - **use_nesterov** (bool) - ǷʹNesterov Accelerated Gradient (NAG)㷨ݶȡΪTrueʹNAGݶȡΪFalseڲʹNAG¸ݶȡĬֵFalse
- - **weight_decay** (float) - Ȩ˥L2 penaltyڵ0Ĭֵ0.0
- - **loss_scale** (float) - ݶϵ0 `loss_scale` תΪͨʹĬֵѵʱʹ `FixedLossScaleManager` `FixedLossScaleManager` `drop_overflow_update` ΪFalseʱֵҪ `FixedLossScaleManager` е `loss_scale` ͬйظϸϢclass`mindspore.FixedLossScaleManager` Ĭֵ1.0
-
- **룺**
-
- **gradients** (tuple[Tensor]) - `params` ݶȣ״shape `params` ͬ
-
- ****
-
- Tensor[bool]ֵΪTrue
-
- **쳣**
-
- - **TypeError** - `learning_rate` intfloatTensorIterableLearningRateSchedule
- - **TypeError** - `parameters` ԪزParameterֵ䡣
- - **TypeError** - `beta1` `beta2` `eps` `loss_scale` float
- - **TypeError** - `weight_decay` floatint
- - **TypeError** - `use_locking` `use_nesterov` bool
- - **ValueError** - `loss_scale` `eps` Сڻ0
- - **ValueError** - `beta1` `beta2` ڣ0.0,1.0Χڡ
- - **ValueError** - `weight_decay` С0
-
- **֧ƽ̨**
-
- ``Ascend`` ``GPU`` ``CPU``
-
- ****
-
- >>> net = Net()
- >>> #1) вʹͬѧϰʺȨ˥
- >>> optim = nn.Adam(params=net.trainable_params())
- >>>
- >>> #2) ʹò鲢òֵͬ
- >>> conv_params = list(filter(lambda x: 'conv' in x.name, net.trainable_params()))
- >>> no_conv_params = list(filter(lambda x: 'conv' not in x.name, net.trainable_params()))
- >>> group_params = [{'params': conv_params, 'weight_decay': 0.01, 'grad_centralization':True},
- ... {'params': no_conv_params, 'lr': 0.01},
- ... {'order_params': net.trainable_params()}]
- >>> optim = nn.Adam(group_params, learning_rate=0.1, weight_decay=0.0)
- >>> # conv_params齫ʹŻеѧϰ0.1Ȩ˥0.01ݶĻTrue
- >>> # no_conv_params齫ʹøѧϰ0.01ŻеȨ˥0.0ݶĻʹĬֵFalse
- >>> # Ż"order_params"õIJ˳²
- >>>
- >>> loss = nn.SoftmaxCrossEntropyWithLogits()
- >>> model = Model(net, loss_fn=loss, optimizer=optim)
-
-
- .. py:method:: target
- :property:
-
- ָhostϻ豸deviceϸ²Ϊstrֻ'CPU''Ascend''GPU'
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