loss

module loss

loss模块是模型训练使用的模块,提供了多个损失函数


cross_entropy(predicts, onehot_targets)

求交叉熵损失

参数:

  • predicts:Var 输出层的预测值,dtype=floatshape=(batch_size, num_classes)

  • onehot_targets:Var onehot编码的标签,dtype=floatshape=(batch_size, num_classes)

返回:交叉熵损失

返回类型:Var

示例

>>> predict = np.random.random([2,3])
>>> onehot = np.array([[1., 0., 0.], [0., 1., 0.]])
>>> nn.loss.cross_entropy(predict, onehot)
array(4.9752955, dtype=float32)

kl(predicts, onehot_targets)

求KL损失

参数:

  • predicts:Var 输出层的预测值,dtype=floatshape=(batch_size, num_classes)

  • onehot_targets:Var onehot编码的标签,dtype=floatshape=(batch_size, num_classes)

返回:KL损失

返回类型:Var

示例

>>> predict = np.random.random([2,3])
>>> onehot = np.array([[1., 0., 0.], [0., 1., 0.]])
>>> nn.loss.kl(predict, onehot)
array(inf, dtype=float32)

mse(predicts, onehot_targets)

求MSE损失

参数:

  • predicts:Var 输出层的预测值,dtype=floatshape=(batch_size, num_classes)

  • onehot_targets:Var onehot编码的标签,dtype=floatshape=(batch_size, num_classes)

返回:MSE损失

返回类型:Var

示例

>>> predict = np.random.random([2,3])
>>> onehot = np.array([[1., 0., 0.], [0., 1., 0.]])
>>> nn.loss.mse(predict, onehot)
array(1.8694793, dtype=float32)

mae(predicts, onehot_targets)

求MAE损失

参数:

  • predicts:Var 输出层的预测值,dtype=floatshape=(batch_size, num_classes)

  • onehot_targets:Var onehot编码的标签,dtype=floatshape=(batch_size, num_classes)

返回:MAE损失

返回类型:Var

示例

>>> predict = np.random.random([2,3])
>>> onehot = np.array([[1., 0., 0.], [0., 1., 0.]])
>>> nn.loss.mae(predict, onehot)
array(2.1805272, dtype=float32)

hinge(predicts, onehot_targets)

求Hinge损失

参数:

  • predicts:Var 输出层的预测值,dtype=floatshape=(batch_size, num_classes)

  • onehot_targets:Var onehot编码的标签,dtype=floatshape=(batch_size, num_classes)

返回:Hinge损失

返回类型:Var

示例

>>> predict = np.random.random([2,3])
>>> onehot = np.array([[1., 0., 0.], [0., 1., 0.]])
>>> nn.loss.hinge(predict, onehot)
array(2.791432, dtype=float32)