tf.metrics.precision_at_thresholds
Computes precision values for different thresholds
on predictions
.
tf.metrics.precision_at_thresholds( labels, predictions, thresholds, weights=None, metrics_collections=None, updates_collections=None, name=None )
The precision_at_thresholds
function creates four local variables, true_positives
, true_negatives
, false_positives
and false_negatives
for various values of thresholds. precision[i]
is defined as the total weight of values in predictions
above thresholds[i]
whose corresponding entry in labels
is True
, divided by the total weight of values in predictions
above thresholds[i]
(true_positives[i] / (true_positives[i] + false_positives[i])
).
For estimation of the metric over a stream of data, the function creates an update_op
operation that updates these variables and returns the precision
.
If weights
is None
, weights default to 1. Use weights of 0 to mask values.
Args | |
---|---|
labels | The ground truth values, a Tensor whose dimensions must match predictions . Will be cast to bool . |
predictions | A floating point Tensor of arbitrary shape and whose values are in the range [0, 1] . |
thresholds | A python list or tuple of float thresholds in [0, 1] . |
weights | Optional Tensor whose rank is either 0, or the same rank as labels , and must be broadcastable to labels (i.e., all dimensions must be either 1 , or the same as the corresponding labels dimension). |
metrics_collections | An optional list of collections that auc should be added to. |
updates_collections | An optional list of collections that update_op should be added to. |
name | An optional variable_scope name. |
Returns | |
---|---|
precision | A float Tensor of shape [len(thresholds)] . |
update_op | An operation that increments the true_positives , true_negatives , false_positives and false_negatives variables that are used in the computation of precision . |
Raises | |
---|---|
ValueError | If predictions and labels have mismatched shapes, or if weights is not None and its shape doesn't match predictions , or if either metrics_collections or updates_collections are not a list or tuple. |
RuntimeError | If eager execution is enabled. |
© 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/r1.15/api_docs/python/tf/metrics/precision_at_thresholds