Keras：将损失和准确性导出为用于绘图的数组

Question

我正在使用以下代码在 Keras 中训练模型：

model_A.fit(train_X, train_Y, epochs=20)

代码运行良好，输出如下：

Epoch 1/20
1800/1800 [==============================] - 0s 34us/step - loss: 0.2764 - acc: 0.9033
Epoch 2/20
1800/1800 [==============================] - 0s 32us/step - loss: 0.2704 - acc: 0.9083
Epoch 3/20
1800/1800 [==============================] - 0s 32us/step - loss: 0.2687 - acc: 0.9094
Epoch 4/20
1800/1800 [==============================] - 0s 32us/step - loss: 0.2748 - acc: 0.9089
Epoch 5/20
1800/1800 [==============================] - 0s 32us/step - loss: 0.2902 - acc: 0.8922
Epoch 6/20
1800/1800 [==============================] - 0s 32us/step - loss: 0.2357 - acc: 0.9183
Epoch 7/20
1800/1800 [==============================] - 0s 32us/step - loss: 0.2499 - acc: 0.9183
Epoch 8/20
1800/1800 [==============================] - 0s 33us/step - loss: 0.2286 - acc: 0.9228
Epoch 9/20
1800/1800 [==============================] - 0s 32us/step - loss: 0.2325 - acc: 0.9194
Epoch 10/20
1800/1800 [==============================] - 0s 33us/step - loss: 0.2053 - acc: 0.9261
Epoch 11/20
1800/1800 [==============================] - 0s 33us/step - loss: 0.2256 - acc: 0.9161
Epoch 12/20
1800/1800 [==============================] - 0s 33us/step - loss: 0.2120 - acc: 0.9261
Epoch 13/20
1800/1800 [==============================] - 0s 32us/step - loss: 0.2085 - acc: 0.9328
Epoch 14/20
1800/1800 [==============================] - 0s 32us/step - loss: 0.1881 - acc: 0.9328
Epoch 15/20
1800/1800 [==============================] - 0s 31us/step - loss: 0.1835 - acc: 0.9344
Epoch 16/20
1800/1800 [==============================] - 0s 34us/step - loss: 0.1812 - acc: 0.9356
Epoch 17/20
1800/1800 [==============================] - 0s 32us/step - loss: 0.1704 - acc: 0.9361
Epoch 18/20
1800/1800 [==============================] - 0s 32us/step - loss: 0.1929 - acc: 0.9272
Epoch 19/20
1800/1800 [==============================] - 0s 32us/step - loss: 0.1822 - acc: 0.9317
Epoch 20/20
1800/1800 [==============================] - 0s 32us/step - loss: 0.1713 - acc: 0.9417

我想知道是否有办法将损失/准确度值保存在数组中，以便稍后将它们绘制在 epoch 上。

Answer 1

fit 方法返回一个 History 对象，其中包含有关训练过程的信息。例如：

# train the model
h = model.fit(...)

# loss values at the end of each epoch
h.history['loss']

# validation loss values per epoch (if you have used validation data)
h.history['val_loss']

# accuracy values at the end of each epoch (if you have used `acc` metric)
h.history['acc']

# validation accuracy values per epoch (if you have used `acc` metric and validation data)
h.history['val_acc']

# list of epochs number
h.epoch

此外，没有必要将History 对象存储在变量中（如h = model.fit(...)），因为它也可以使用model.history.history 访问（但是，请注意，在模型中不会保留此history 属性）使用model.save(...)保存）。