# Unique
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## The goal


Questions to [David Rotermund](mailto:davrot@uni-bremen.de)


## [numpy.unique](https://numpy.org/doc/stable/reference/generated/numpy.unique.html)

```python
numpy.unique(ar, return_index=False, return_inverse=False, return_counts=False, axis=None, *, equal_nan=True)
```

> Find the unique elements of an array.
> 
> 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