I add a callback to decay learning rate:
keras.callbacks.ReduceLROnPlateau(monitor=\'val_loss\', factor=0.5, patience=100,
v
According to the author of Keras, the proper way is to subclass the TensorBoard
callback:
from keras import backend as K
from keras.callbacks import TensorBoard
class LRTensorBoard(TensorBoard):
def __init__(self, log_dir, **kwargs): # add other arguments to __init__ if you need
super().__init__(log_dir=log_dir, **kwargs)
def on_epoch_end(self, epoch, logs=None):
logs = logs or {}
logs.update({'lr': K.eval(self.model.optimizer.lr)})
super().on_epoch_end(epoch, logs)
Then pass it as part of the callbacks
argument to model.fit
(credit Finncent Price):
model.fit(x=..., y=..., callbacks=[LRTensorBoard(log_dir="/tmp/tb_log")])
class XTensorBoard(TensorBoard):
def on_epoch_begin(self, epoch, logs=None):
# get values
lr = float(K.get_value(self.model.optimizer.lr))
decay = float(K.get_value(self.model.optimizer.decay))
# computer lr
lr = lr * (1. / (1 + decay * epoch))
K.set_value(self.model.optimizer.lr, lr)
def on_epoch_end(self, epoch, logs=None):
logs = logs or {}
logs['lr'] = K.get_value(self.model.optimizer.lr)
super().on_epoch_end(epoch, logs)
callbacks_list = [XTensorBoard('./logs')]
model.fit(X_train, y_train, validation_data=(X_test, y_test), epochs=20, batch_size=32, verbose=2, callbacks=callbacks_list)
lr curve in tensorboard
You gave the optimizer's code twice, instead of TensorBoard Callback. Anyway, I didn`t find the way to display the learning rate on TensorBoard. I am plotting it after the training finished, taking data from History object:
nb_epoch = len(history1.history['loss'])
learning_rate=history1.history['lr']
xc=range(nb_epoch)
plt.figure(3,figsize=(7,5))
plt.plot(xc,learning_rate)
plt.xlabel('num of Epochs')
plt.ylabel('learning rate')
plt.title('Learning rate')
plt.grid(True)
plt.style.use(['seaborn-ticks'])
The chart looks like this: LR plot
Sorry, that is not exactly what you are asking about, but perhaps could help.
Note that with the current nightly version of tf (2.5 - probably earlier) learning rates using LearningRateSchedule are automatically added to tensorboard's logs. The following solution is only necessary if you're adapting the learning rate some other way - e.g. via ReduceLROnPlateau or LearningRateScheduler (different to LearningRateSchedule) callbacks.
While extending tf.keras.callbacks.TensorBoard
is a viable option, I prefer composition over subclassing.
class LearningRateLogger(tf.keras.callbacks.Callback):
def __init__(self):
super().__init__()
self._supports_tf_logs = True
def on_epoch_end(self, epoch, logs=None):
if logs is None or "learning_rate" in logs:
return
logs["learning_rate"] = self.model.optimizer.lr
This allows us to compose multiple similar callbacks, and use the logged learning rate in multiple other callbacks (e.g. if you add a CSVLogger it should also write the learning rate values to file).
Then in model.fit
model.fit(
callbacks=[
LearningRateLogger(),
# other callbacks that update `logs`
tf.keras.callbacks.TensorBoard(path),
# other callbacks that use updated logs, e.g. CSVLogger
],
**kwargs
)