Sort a sequence of keys in lexicographic order.
JAX implementation of numpy.lexsort()
.
An array of integers of shape keys[0].shape
giving the indices of the entries in lexicographically-sorted order.
Examples
lexsort()
with a single key is equivalent to argsort()
:
>>> key1 = jnp.array([4, 2, 3, 2, 5]) >>> jnp.lexsort([key1]) Array([1, 3, 2, 0, 4], dtype=int32) >>> jnp.argsort(key1) Array([1, 3, 2, 0, 4], dtype=int32)
With multiple keys, lexsort()
uses the last key as the primary key:
>>> key2 = jnp.array([2, 1, 1, 2, 2]) >>> jnp.lexsort([key1, key2]) Array([1, 2, 3, 0, 4], dtype=int32)
The meaning of the indices become more clear when printing the sorted keys:
>>> indices = jnp.lexsort([key1, key2]) >>> print(f"{key1[indices]}\n{key2[indices]}") [2 3 2 4 5] [1 1 2 2 2]
Notice that the elements of key2
appear in order, and within the sequences of duplicated values the corresponding elements of `key1
appear in order.
For multi-dimensional inputs, lexsort()
defaults to sorting along the last axis:
>>> key1 = jnp.array([[2, 4, 2, 3], ... [3, 1, 2, 2]]) >>> key2 = jnp.array([[1, 2, 1, 3], ... [2, 1, 2, 1]]) >>> jnp.lexsort([key1, key2]) Array([[0, 2, 1, 3], [1, 3, 2, 0]], dtype=int32)
A different sort axis can be chosen using the axis
keyword; here we sort along the leading axis:
>>> jnp.lexsort([key1, key2], axis=0) Array([[0, 1, 0, 1], [1, 0, 1, 0]], dtype=int32)
RetroSearch is an open source project built by @garambo | Open a GitHub Issue
Search and Browse the WWW like it's 1997 | Search results from DuckDuckGo
HTML:
3.2
| Encoding:
UTF-8
| Version:
0.7.4