diff --git a/docs/programming_guide/source_en/initializer.md b/docs/programming_guide/source_en/initializer.md index cd934f345ffd31fe2502207806817a392642f10c..58cdabbc0356da398ee9f18d9f8b32628fb4fac0 100644 --- a/docs/programming_guide/source_en/initializer.md +++ b/docs/programming_guide/source_en/initializer.md @@ -1,5 +1,314 @@ -# Initialization of Network Parameters +# Initialization of Network Parameters -No English version right now, welcome to contribute. +[![](https://gitee.com/mindspore/docs/raw/master/resource/_static/logo_source.png)](https://gitee.com/mindspore/docs/blob/master/docs/programming_guide/source_zh_cn/initializer.ipynb) [![](https://gitee.com/mindspore/docs/raw/master/resource/_static/logo_notebook.png)](https://obs.dualstack.cn-north-4.myhuaweicloud.com/mindspore-website/notebook/master/programming_guide/mindspore_initializer.ipynb) [![](https://gitee.com/mindspore/docs/raw/master/resource/_static/logo_modelarts.png)](https://authoring-modelarts-cnnorth4.huaweicloud.com/console/lab?share-url-b64=aHR0cHM6Ly9vYnMuZHVhbHN0YWNrLmNuLW5vcnRoLTQubXlodWF3ZWljbG91ZC5jb20vbWluZHNwb3JlLXdlYnNpdGUvbm90ZWJvb2svbW9kZWxhcnRzL3Byb2dyYW1taW5nX2d1aWRlL21pbmRzcG9yZV9pbml0aWFsaXplci5pcHluYg==&imagename=MindSpore1.1.1) + +## Overview + +MindSpore provides weight initialization module which allows initializing network parameters by encapsulating operators and initializer functions such as String, Subclass of Initializer, Customizing Tensor. Initializer is the base class for initialization in MindSpore. The subclass of Initializer include various distribution(Zero, One, XavierUniform, HeUniform, HeNormal, Constant, Uniform, Normal, TruncatedNormal). +Then, encapsulating operators and initializer function are introduced in detail. + +## Initializing parameters by encapsulating operators +Mindspore provides different ways to initialize parameters, and encapsulates the parameters initialization function in some operators. This section will introduce how to Initializing parameters by the operators which has parameters initialization function, Taking `conv2D` operator as an example, introducing Initializing parameters by String, Subclass of `Initializer`, Customizing `Tensor`, etc respectively. +In the following example, the `Normal` is a subclass of `Initializer` and can be replaced by any subclasses of `Initializer`. + +### String +The string’s content should be as same as the name of the subclass of `Initializer` and the default arguments in the subclass of `Initializer` will be used when initializing network parameters by string. For example, using the string `Normal` is equivalent to using the subclass `Normal` of `Initializer`. The code is as follows: + + +```python +import numpy as np +import mindspore.nn as nn +from mindspore import Tensor +from mindspore.common import set_seed + +set_seed(1) + +input_data = Tensor(np.ones([1, 3, 16, 50], dtype=np.float32)) +net = nn.Conv2d(3, 64, 3, weight_init='Normal') +output = net(input_data) +print(output) +``` + + [[[[ 3.10382620e-02 4.38603461e-02 4.38603461e-02 ... 4.38603461e-02 + 4.38603461e-02 1.38719045e-02] + [ 3.26051228e-02 3.54298912e-02 3.54298912e-02 ... 3.54298912e-02 + 3.54298912e-02 -5.54019120e-03] + [ 3.26051228e-02 3.54298912e-02 3.54298912e-02 ... 3.54298912e-02 + 3.54298912e-02 -5.54019120e-03] + ... + [ 3.26051228e-02 3.54298912e-02 3.54298912e-02 ... 3.54298912e-02 + 3.54298912e-02 -5.54019120e-03] + [ 3.26051228e-02 3.54298912e-02 3.54298912e-02 ... 3.54298912e-02 + 3.54298912e-02 -5.54019120e-03] + [ 9.66199022e-03 1.24104535e-02 1.24104535e-02 ... 1.24104535e-02 + 1.24104535e-02 -1.38977719e-02]] + + ... + + [[ 3.98553275e-02 -1.35465711e-03 -1.35465711e-03 ... -1.35465711e-03 + -1.35465711e-03 -1.00310734e-02] + [ 4.38403059e-03 -3.60766202e-02 -3.60766202e-02 ... -3.60766202e-02 + -3.60766202e-02 -2.95619294e-02] + [ 4.38403059e-03 -3.60766202e-02 -3.60766202e-02 ... -3.60766202e-02 + -3.60766202e-02 -2.95619294e-02] + ... + [ 4.38403059e-03 -3.60766202e-02 -3.60766202e-02 ... -3.60766202e-02 + -3.60766202e-02 -2.95619294e-02] + [ 4.38403059e-03 -3.60766202e-02 -3.60766202e-02 ... -3.60766202e-02 + -3.60766202e-02 -2.95619294e-02] + [ 1.33139016e-02 6.74417242e-05 6.74417242e-05 ... 6.74417242e-05 + 6.74417242e-05 -2.27325838e-02]]]] + + +### The subclass of Initializer +Initializing network parameters by the subclass of `Initializer` is similar to Initializing network parameters by string. The difference is that Initializing network parameters by string will use the default arguments of the subclass of `Initializer`. To assign the arguments in the subclass of `Initializer`, you must instantiate the subclass of `Initializer`, Take `Normal(0.2)` as an example. The code is as follows: + + +```python +import numpy as np +import mindspore.nn as nn +from mindspore import Tensor +from mindspore.common import set_seed +from mindspore.common.initializer import Normal + +set_seed(1) + +input_data = Tensor(np.ones([1, 3, 16, 50], dtype=np.float32)) +net = nn.Conv2d(3, 64, 3, weight_init=Normal(0.2)) +output = net(input_data) +print(output) +``` + + [[[[ 6.2076533e-01 8.7720710e-01 8.7720710e-01 ... 8.7720710e-01 + 8.7720710e-01 2.7743810e-01] + [ 6.5210247e-01 7.0859784e-01 7.0859784e-01 ... 7.0859784e-01 + 7.0859784e-01 -1.1080378e-01] + [ 6.5210247e-01 7.0859784e-01 7.0859784e-01 ... 7.0859784e-01 + 7.0859784e-01 -1.1080378e-01] + ... + [ 6.5210247e-01 7.0859784e-01 7.0859784e-01 ... 7.0859784e-01 + 7.0859784e-01 -1.1080378e-01] + [ 6.5210247e-01 7.0859784e-01 7.0859784e-01 ... 7.0859784e-01 + 7.0859784e-01 -1.1080378e-01] + [ 1.9323981e-01 2.4820906e-01 2.4820906e-01 ... 2.4820906e-01 + 2.4820906e-01 -2.7795550e-01]] + + ... + + [[ 7.9710668e-01 -2.7093157e-02 -2.7093157e-02 ... -2.7093157e-02 + -2.7093157e-02 -2.0062150e-01] + [ 8.7680638e-02 -7.2153252e-01 -7.2153252e-01 ... -7.2153252e-01 + -7.2153252e-01 -5.9123868e-01] + [ 8.7680638e-02 -7.2153252e-01 -7.2153252e-01 ... -7.2153252e-01 + -7.2153252e-01 -5.9123868e-01] + ... + [ 8.7680638e-02 -7.2153252e-01 -7.2153252e-01 ... -7.2153252e-01 + -7.2153252e-01 -5.9123868e-01] + [ 8.7680638e-02 -7.2153252e-01 -7.2153252e-01 ... -7.2153252e-01 + -7.2153252e-01 -5.9123868e-01] + [ 2.6627803e-01 1.3488382e-03 1.3488382e-03 ... 1.3488382e-03 + 1.3488382e-03 -4.5465171e-01]]]] + + +### Custom Tensor +In addition to the above two initialization methods, users can initialize network parameters by customizing `Tensor` when parameters need to be initialized by data types not available in MindSpore. The code is as follows: + + +```python +import numpy as np +import mindspore.nn as nn +from mindspore import Tensor +from mindspore import dtype as mstype + +weight = Tensor(np.ones([64, 3, 3, 3]), dtype=mstype.float32) +input_data = Tensor(np.ones([1, 3, 16, 50], dtype=np.float32)) +net = nn.Conv2d(3, 64, 3, weight_init=weight) +output = net(input_data) +print(output) +``` + + [[[[12. 18. 18. ... 18. 18. 12.] + [18. 27. 27. ... 27. 27. 18.] + [18. 27. 27. ... 27. 27. 18.] + ... + [18. 27. 27. ... 27. 27. 18.] + [18. 27. 27. ... 27. 27. 18.] + [12. 18. 18. ... 18. 18. 12.]] + + ... + + [[12. 18. 18. ... 18. 18. 12.] + [18. 27. 27. ... 27. 27. 18.] + [18. 27. 27. ... 27. 27. 18.] + ... + [18. 27. 27. ... 27. 27. 18.] + [18. 27. 27. ... 27. 27. 18.] + [12. 18. 18. ... 18. 18. 12.]]]] + + +## Initializing parameters by initializer functions + +In the code sample above, demonstrating some methods about how to initialize networks parameters, for example, the parameters `weight_init` will pass into the `Conv2d` operator when `Conv2d` is encapsulated by NN layer and the `Conv2d` operator will invoke `initializer` function encapsulated in `Parameter` class to complele initializing parameters When the operator is initialized. However, some operators do not encapsulate the function of parameters initialization internally like `Conv2D`. For example, the weight of `conv3D` operator is passed into 'conv3D' operator as parameters. In this case, it is necessary to define the initialization of weight manually. + +When the parameters is initialized, the `Initializer` method can be used to initialize the parameter by calling different data types in the subclass of `Initializer` to get different types of data. + +When using initializer for parameter initialization, supporting for the passing parameters are `init`, `shape`, `dtype` : + +- `init`：Support passing in `Tensor`, `str`, the subclass of `Initializer`. + +- `shape`：Support passing in `list`, `tuple`, `int`. + +- `dtype`：Support passing in `mindspore.dtype`。 + +### The init parameter is Tensor + + The code is as follows： + +```python +import numpy as np +from mindspore import Tensor +from mindspore import dtype as mstype +from mindspore.common import set_seed +from mindspore.common.initializer import initializer +from mindspore.ops.operations import nn_ops as nps + +set_seed(1) + +input_data = Tensor(np.ones([16, 3, 10, 32, 32]), dtype=mstype.float32) +weight_init = Tensor(np.ones([32, 3, 4, 3, 3]), dtype=mstype.float32) +weight = initializer(weight_init, shape=[32, 3, 4, 3, 3]) +conv3d = nps.Conv3D(out_channel=32, kernel_size=(4, 3, 3)) +output = conv3d(input_data, weight) +print(output) +``` + +output： + +```text +[[[[[108 108 108 ... 108 108 108] + [108 108 108 ... 108 108 108] + [108 108 108 ... 108 108 108] + ... + [108 108 108 ... 108 108 108] + [108 108 108 ... 108 108 108] + [108 108 108 ... 108 108 108]] + ... + [[108 108 108 ... 108 108 108] + [108 108 108 ... 108 108 108] + [108 108 108 ... 108 108 108] + ... + [108 108 108 ... 108 108 108] + [108 108 108 ... 108 108 108] + [108 108 108 ... 108 108 108]]]]] +``` + +### The init parameter is string + + The code is as follows： + +```python +import numpy as np +from mindspore import Tensor +from mindspore import dtype as mstype +from mindspore.common import set_seed +from mindspore.common.initializer import initializer +from mindspore.ops.operations import nn_ops as nps + +set_seed(1) + +input_data = Tensor(np.ones([16, 3, 10, 32, 32]), dtype=mstype.float32) +weight = initializer('Normal', shape=[32, 3, 4, 3, 3], dtype=mstype.float32) +conv3d = nps.Conv3D(out_channel=32, kernel_size=(4, 3, 3)) +output = conv3d(input_data, weight) +print(output) +``` + +output: + +```text +[[[[[0 0 0 ... 0 0 0] + [0 0 0 ... 0 0 0] + [0 0 0 ... 0 0 0]] + ... + [0 0 0 ... 0 0 0] + [0 0 0 ... 0 0 0] + [0 0 0 ... 0 0 0]] + ... + [[0 0 0 ... 0 0 0] + [0 0 0 ... 0 0 0] + [0 0 0 ... 0 0 0]] + ... + [0 0 0 ... 0 0 0] + [0 0 0 ... 0 0 0] + [0 0 0 ... 0 0 0]]]]] +``` + +### The init parameter is a subclass of Initializer + + The code is as follows： + +```python +import numpy as np +from mindspore import Tensor +from mindspore import dtype as mstype +from mindspore.common import set_seed +from mindspore.ops.operations import nn_ops as nps +from mindspore.common.initializer import Normal, initializer + +set_seed(1) + +input_data = Tensor(np.ones([16, 3, 10, 32, 32]), dtype=mstype.float32) +weight = initializer(Normal(0.2), shape=[32, 3, 4, 3, 3], dtype=mstype.float32) +conv3d = nps.Conv3D(out_channel=32, kernel_size=(4, 3, 3)) +output = conv3d(input_data, weight) +print(output) +``` + +```text +[[[[[0 0 0 ... 0 0 0] + [0 0 0 ... 0 0 0] + [0 0 0 ... 0 0 0]] + ... + [0 0 0 ... 0 0 0] + [0 0 0 ... 0 0 0] + [0 0 0 ... 0 0 0]] + ... + [[0 0 0 ... 0 0 0] + [0 0 0 ... 0 0 0] + [0 0 0 ... 0 0 0]] + ... + [0 0 0 ... 0 0 0] + [0 0 0 ... 0 0 0] + [0 0 0 ... 0 0 0]]]]] +``` + +### Parameter example + + The code is as follows： + + +```python +import numpy as np +from mindspore import dtype as mstype +from mindspore.common import set_seed +from mindspore.ops import operations as ops +from mindspore import Tensor, Parameter, context +from mindspore.common.initializer import Normal, initializer + +set_seed(1) + +weight1 = Parameter(initializer('Normal', [5, 4], mstype.float32), name="w1") +weight2 = Parameter(initializer(Normal(0.2), [5, 4], mstype.float32), name="w2") +input_data = Tensor(np.arange(20).reshape(5, 4), dtype=mstype.float32) +net = ops.Add() +output = net(input_data, weight1) +output = net(output, weight2) +print(output) +``` + + [[-0.3305102 1.0412874 2.0412874 3.0412874] + [ 4.0412874 4.9479127 5.9479127 6.9479127] + [ 7.947912 9.063009 10.063009 11.063009 ] + [12.063009 13.536987 14.536987 14.857441 ] + [15.751231 17.073082 17.808317 19.364822 ]] - \ No newline at end of file