<br />

|---|
| [![](https://www.tensorflow.org/images/GitHub-Mark-32px.png) View source on GitHub](https://github.com/keras-team/keras/tree/v2.15.0/keras/src/callbacks.py#L3007-L3144) |

Reduce learning rate when a metric has stopped improving.

Inherits From: [`Callback`](https://www.tensorflow.org/versions/r2.15/api_docs/python/tf/keras/callbacks/Callback.md.txt)

```python
tf.keras.callbacks.ReduceLROnPlateau(
    monitor='val_loss',
    factor=0.1,
    patience=10,
    verbose=0,
    mode='auto',
    min_delta=0.0001,
    cooldown=0,
    min_lr=0,
    **kwargs
)
```

Models often benefit from reducing the learning rate by a factor
of 2-10 once learning stagnates. This callback monitors a
quantity and if no improvement is seen for a 'patience' number
of epochs, the learning rate is reduced.

#### Example:

```python
reduce_lr = ReduceLROnPlateau(monitor='val_loss', factor=0.2,
                              patience=5, min_lr=0.001)
model.fit(X_train, Y_train, callbacks=[reduce_lr])
```

<br />

<br />

<br />

| ## Args ||
|---|---|
| `monitor` | quantity to be monitored. |
| `factor` | factor by which the learning rate will be reduced. `new_lr = lr * factor`. |
| `patience` | number of epochs with no improvement after which learning rate will be reduced. |
| `verbose` | int. 0: quiet, 1: update messages. |
| `mode` | one of `{'auto', 'min', 'max'}`. In `'min'` mode, the learning rate will be reduced when the quantity monitored has stopped decreasing; in `'max'` mode it will be reduced when the quantity monitored has stopped increasing; in `'auto'` mode, the direction is automatically inferred from the name of the monitored quantity. |
| `min_delta` | threshold for measuring the new optimum, to only focus on significant changes. |
| `cooldown` | number of epochs to wait before resuming normal operation after lr has been reduced. |
| `min_lr` | lower bound on the learning rate. |

<br />

## Methods

### `in_cooldown`

[View source](https://github.com/keras-team/keras/tree/v2.15.0/keras/src/callbacks.py#L3143-L3144)

```python
in_cooldown()
```

### `set_model`

[View source](https://github.com/keras-team/keras/tree/v2.15.0/keras/src/callbacks.py#L694-L695)

```python
set_model(
    model
)
```

### `set_params`

[View source](https://github.com/keras-team/keras/tree/v2.15.0/keras/src/callbacks.py#L691-L692)

```python
set_params(
    params
)
```