jax.numpy.uniqueΒΆ

jax.numpy.unique(ar, return_index=False, return_inverse=False, return_counts=False, axis=None, *, size=None)[source]ΒΆ

Find the unique elements of an array.

LAX-backend implementation of unique().

Because the size of the output of unique is data-dependent, the function is not typically compatible with JIT. The JAX version adds the optional size argument which specifies the size of the data-dependent output arrays: it must be specified statically for jnp.unique to be traced. If specified, the first size unique elements will be returned; if there are fewer unique elements than size indicates, the return value will be padded with the minimum value in the input array.

The size cannot currently be used with the axis argument.

Original docstring below.

Returns the sorted unique elements of an array. There are three optional outputs in addition to the unique elements:

  • the indices of the input array that give the unique values

  • the indices of the unique array that reconstruct the input array

  • the number of times each unique value comes up in the input array

Parameters
  • ar (array_like) – Input array. Unless axis is specified, this will be flattened if it is not already 1-D.

  • return_index (bool, optional) – If True, also return the indices of ar (along the specified axis, if provided, or in the flattened array) that result in the unique array.

  • return_inverse (bool, optional) – If True, also return the indices of the unique array (for the specified axis, if provided) that can be used to reconstruct ar.

  • return_counts (bool, optional) – If True, also return the number of times each unique item appears in ar.

  • axis (Optional[int]) –

Returns

  • unique (ndarray) – The sorted unique values.

  • unique_indices (ndarray, optional) – The indices of the first occurrences of the unique values in the original array. Only provided if return_index is True.

  • unique_inverse (ndarray, optional) – The indices to reconstruct the original array from the unique array. Only provided if return_inverse is True.

  • unique_counts (ndarray, optional) – The number of times each of the unique values comes up in the original array. Only provided if return_counts is True.

    New in version 1.9.0.