Differences with torch.nn.CrossEntropyLoss

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torch.nn.CrossEntropyLoss

class torch.nn.CrossEntropyLoss(
    weight=None,
    size_average=None,
    ignore_index=-100,
    reduce=None,
    reduction='mean'
)(input, target) -> Tensor

For more information, see torch.nn.CrossEntropyLoss.

mindspore.nn.CrossEntropyLoss

class mindspore.nn.CrossEntropyLoss(
    weight=None,
    ignore_index=-100,
    reduction='mean',
    label_smoothing=0.0
)(logits, labels) -> Tensor

For more information, see mindspore.nn.CrossEntropyLoss.

Differences

PyTorch: Calculate the cross-entropy loss between the predicted and target values.

MindSpore: MindSpore implements the same function as PyTorch, and the target value supports two different data forms: class index and class probabilistic.

Categories

Subcategories

PyTorch

MindSpore

Difference

Parameters

Parameter 1

weight

weight

-

Parameter 2

size_average

-

PyTorch has deprecated this parameter, function taken over by reduction

Parameter 3

ignore_index

ignore_index

-

Parameter 4

reduce

-

PyTorch has deprecated this parameter, function taken over by reduction

Parameter 5

reduction

reduction

-

Parameter 6

-

label_smoothing

Label smoothing value, used as a regularization means to prevent overfitting of the model when calculating Loss. The range of values is [0.0, 1.0]. Default value: 0.0.

Input

Input 1

input

logits

Same function, different parameter names

Input 2

target

labels

Same function, different parameter names

Code Example

Both PyTorch and MindSpore support the case where the target value is class index.

# PyTorch
import torch
import numpy as np

input_torch = np.array([[1.624, -0.611, -0.528, -1.072, 0.865], [-2.301, 1.744, -0.761, 0.319, -0.249], [1.462, -2.060, -0.322, -0.384, 1.133]])
target_torch = np.array([1, 0, 4])
loss = torch.nn.CrossEntropyLoss()
input_torch = torch.tensor(input_torch, requires_grad=True)
target_torch = torch.tensor(target_torch, dtype=torch.long)
output = loss(input_torch, target_torch)
print(round(float(output.detach().numpy()), 3))
# 2.764

# MindSpore
import mindspore
import numpy as np

input_ms = np.array([[1.624, -0.611, -0.528, -1.072, 0.865], [-2.301, 1.744, -0.761, 0.319, -0.249], [1.462, -2.060, -0.322, -0.384, 1.133]])
target_ms = np.array([1, 0, 4])
input_ms = mindspore.Tensor(input_ms, mindspore.float32)
target_ms = mindspore.Tensor(target_ms, mindspore.int32)
loss = mindspore.nn.CrossEntropyLoss()
output = loss(input_ms, target_ms)
print(round(float(output), 3))
# 2.764