# tf.contrib.metrics.streaming_accuracy(predictions, labels, weights=None, metrics_collections=None, updates_collections=None, name=None)

### tf.contrib.metrics.streaming_accuracy(predictions, labels, weights=None, metrics_collections=None, updates_collections=None, name=None)

See the guide: Metrics (contrib) > Metric Ops

Calculates how often predictions matches labels.

The streaming_accuracy function creates two local variables, total and count that are used to compute the frequency with which predictions matches labels. This frequency is ultimately returned as accuracy: an idempotent operation that simply divides total by count.

For estimation of the metric over a stream of data, the function creates an update_op operation that updates these variables and returns the accuracy. Internally, an is_correct operation computes a Tensor with elements 1.0 where the corresponding elements of predictions and labels match and 0.0 otherwise. Then update_op increments total with the reduced sum of the product of weights and is_correct, and it increments count with the reduced sum of weights.

If weights is None, weights default to 1. Use weights of 0 to mask values.

#### Args:

• predictions: The predicted values, a Tensor of any shape.
• labels: The ground truth values, a Tensor whose shape matches predictions.
• weights: 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 accuracy 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:

• accuracy: A Tensor representing the accuracy, the value of total divided by count.
• update_op: An operation that increments the total and count variables appropriately and whose value matches accuracy.

#### 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.