uniq¶

pydl.uniq(x, index=None)[source]¶

Replicates the IDL UNIQ() function.

Returns the subscripts of the unique elements of an array. The elements must actually be sorted before being passed to this function. This can be done by sorting x explicitly or by passing the array subscripts that sort x as a second parameter.

Parameters

xarray-like: Search this array for unique items.
indexarray-like, optional: This array provides the array subscripts that sort x.

Returns

array-like: The subscripts of x that are the unique elements of x.

Notes

Given a sorted array, and assuming that there is a set of adjacent identical items, uniq() will return the subscript of the last unique item. This charming feature is retained for reproducibility.

References

http://www.harrisgeospatial.com/docs/uniq.html

Examples

>>> import numpy as np
>>> from pydl import uniq
>>> data = np.array([ 1, 2, 3, 1, 5, 6, 1, 7, 3, 2, 5, 9, 11, 1 ])
>>> print(uniq(np.sort(data)))
[ 3  5  7  9 10 11 12 13]

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uniq¶