Computes best recall where precision is >= specified value.
Inherits From: Metric, Layer, Module
tf.keras.metrics.RecallAtPrecision(
precision, num_thresholds=200, name=None, dtype=None
)
For a given score-label-distribution the required precision might not be achievable, in this case 0.0 is returned as recall.
This metric creates four local variables, true_positives, true_negatives, false_positives and false_negatives that are used to compute the recall at the given precision. The threshold for the given precision value is computed and used to evaluate the corresponding recall.
If sample_weight is None, weights default to 1. Use sample_weight of 0 to mask values.
| Args | |
|---|---|
precision | A scalar value in range [0, 1]. |
num_thresholds | (Optional) Defaults to 200. The number of thresholds to use for matching the given precision. |
name | (Optional) string name of the metric instance. |
dtype | (Optional) data type of the metric result. |
m = tf.keras.metrics.RecallAtPrecision(0.8) m.update_state([0, 0, 1, 1], [0, 0.5, 0.3, 0.9]) m.result().numpy() 0.5
m.reset_states()
m.update_state([0, 0, 1, 1], [0, 0.5, 0.3, 0.9],
sample_weight=[1, 0, 0, 1])
m.result().numpy()
1.0
Usage with compile() API:
model.compile(
optimizer='sgd',
loss='mse',
metrics=[tf.keras.metrics.RecallAtPrecision(precision=0.8)])
reset_statesreset_states()
Resets all of the metric state variables.
This function is called between epochs/steps, when a metric is evaluated during training.
resultresult()
Computes and returns the metric value tensor.
Result computation is an idempotent operation that simply calculates the metric value using the state variables.
update_state
update_state(
y_true, y_pred, sample_weight=None
)
Accumulates confusion matrix statistics.
| Args | |
|---|---|
y_true | The ground truth values. |
y_pred | The predicted values. |
sample_weight | Optional weighting of each example. Defaults to 1. Can be a Tensor whose rank is either 0, or the same rank as y_true, and must be broadcastable to y_true. |
| Returns | |
|---|---|
| Update op. |
© 2020 The TensorFlow Authors. All rights reserved.
Licensed under the Creative Commons Attribution License 3.0.
Code samples licensed under the Apache 2.0 License.
https://www.tensorflow.org/versions/r2.4/api_docs/python/tf/keras/metrics/RecallAtPrecision