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| ``mx.symbol.L2Normalization`` |
| ========================================================== |
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| Description |
| ---------------------- |
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| Normalize the input array using the L2 norm. |
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| For 1-D NDArray, it computes:: |
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| out = data / sqrt(sum(data ** 2) + eps) |
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| For N-D NDArray, if the input array has shape (N, N, ..., N), |
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| with ``mode`` = ``instance``, it normalizes each instance in the multidimensional |
| array by its L2 norm.:: |
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| for i in 0...N |
| out[i,:,:,...,:] = data[i,:,:,...,:] / sqrt(sum(data[i,:,:,...,:] ** 2) + eps) |
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| with ``mode`` = ``channel``, it normalizes each channel in the array by its L2 norm.:: |
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| for i in 0...N |
| out[:,i,:,...,:] = data[:,i,:,...,:] / sqrt(sum(data[:,i,:,...,:] ** 2) + eps) |
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| with ``mode`` = ``spatial``, it normalizes the cross channel norm for each position |
| in the array by its L2 norm.:: |
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| for dim in 2...N |
| for i in 0...N |
| out[.....,i,...] = take(out, indices=i, axis=dim) / sqrt(sum(take(out, indices=i, axis=dim) ** 2) + eps) |
| -dim- |
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| **Example**:: |
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| x = [[[1,2], |
| [3,4]], |
| [[2,2], |
| [5,6]]] |
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| L2Normalization(x, mode='instance') |
| =[[[ 0.18257418 0.36514837] |
| [ 0.54772252 0.73029673]] |
| [[ 0.24077171 0.24077171] |
| [ 0.60192931 0.72231513]]] |
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| L2Normalization(x, mode='channel') |
| =[[[ 0.31622776 0.44721359] |
| [ 0.94868326 0.89442718]] |
| [[ 0.37139067 0.31622776] |
| [ 0.92847669 0.94868326]]] |
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| L2Normalization(x, mode='spatial') |
| =[[[ 0.44721359 0.89442718] |
| [ 0.60000002 0.80000001]] |
| [[ 0.70710677 0.70710677] |
| [ 0.6401844 0.76822126]]] |
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| Usage |
| ---------- |
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| .. code:: r |
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| mx.symbol.L2Normalization(...) |
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| Arguments |
| ------------------ |
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| +----------------------------------------+------------------------------------------------------------+ |
| | Argument | Description | |
| +========================================+============================================================+ |
| | ``data`` | NDArray-or-Symbol. | |
| | | | |
| | | Input array to normalize. | |
| +----------------------------------------+------------------------------------------------------------+ |
| | ``eps`` | float, optional, default=1.00000001e-10. | |
| | | | |
| | | A small constant for numerical stability. | |
| +----------------------------------------+------------------------------------------------------------+ |
| | ``mode`` | {'channel', 'instance', 'spatial'},optional, | |
| | | default='instance'. | |
| | | | |
| | | Specify the dimension along which to compute L2 norm. | |
| +----------------------------------------+------------------------------------------------------------+ |
| | ``name`` | string, optional. | |
| | | | |
| | | Name of the resulting symbol. | |
| +----------------------------------------+------------------------------------------------------------+ |
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| Value |
| ---------- |
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| ``out`` The result mx.symbol |
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| Link to Source Code: http://github.com/apache/incubator-mxnet/blob/1.6.0/src/operator/l2_normalization.cc#L196 |
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