tf.unique

tf.unique(
    x,
    out_idx=tf.int32,
    name=None
)

Defined in tensorflow/python/ops/array_ops.py.

See the guide: Math > Sequence Comparison and Indexing

Finds unique elements in a 1-D tensor.

This operation returns a tensor y containing all of the unique elements of x sorted in the same order that they occur in x. This operation also returns a tensor idx the same size as x that contains the index of each value of x in the unique output y. In other words:

y[idx[i]] = x[i] for i in [0, 1,...,rank(x) - 1]

For example:

# tensor 'x' is [1, 1, 2, 4, 4, 4, 7, 8, 8]
y, idx = unique(x)
y ==> [1, 2, 4, 7, 8]
idx ==> [0, 0, 1, 2, 2, 2, 3, 4, 4]

Args:

• x: A Tensor. 1-D.
• out_idx: An optional tf.DType from: tf.int32, tf.int64. Defaults to tf.int32.
• name: A name for the operation (optional).

Returns:

A tuple of Tensor objects (y, idx).

• y: A Tensor. Has the same type as x.
• idx: A Tensor of type out_idx.