tf.keras.metrics.SparseCategoricalAccuracy

Calculates how often predictions match integer labels.

Inherits From: Mean, Metric, Layer, Module

Used in the notebooks

Used in the guide Used in the tutorials
acc = np.dot(sample_weight, np.equal(y_true, np.argmax(y_pred, axis=1))

You can provide logits of classes as y_pred, since argmax of logits and probabilities are same.

This metric creates two local variables, total and count that are used to compute the frequency with which y_pred matches y_true. This frequency is ultimately returned as sparse categorical accuracy: an idempotent operation that simply divides total by count.

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

name (Optional) string name of the metric instance.
dtype (Optional) data type of the metric result.

Standalone usage:

m = tf.keras.metrics.SparseCategoricalAccuracy()
m.update_state([[2], [1]], [[0.1, 0.6, 0.3], [0.05, 0.95, 0]])
m.result().numpy()
0.5
m.reset_state()
m.update_state([[2], [1]], [[0.1, 0.6, 0.3], [0.05, 0.95, 0]],
               sample_weight=[0.7, 0.3])
m.result().numpy()
0.3

Usage with compile() API:

model.compile(
    optimizer='sgd',
    loss='mse',
    metrics=[tf.keras.metrics.SparseCategoricalAccuracy()])

Methods

reset_state

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Resets all of the metric state variables.

This function is called between epochs/steps, when a metric is evaluated during training.

result

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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

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