papyri
{ } Raw JSON

bundles / numpy 2.4.4 / numpy / lib / _index_tricks_impl / IndexExpression

class

numpy.lib._index_tricks_impl:IndexExpression

source: /numpy/lib/_index_tricks_impl.py :723

Signature

class   IndexExpression ( maketuple )

Members

Summary

A nicer way to build up index tuples for arrays.

Extended Summary

For any index combination, including slicing and axis insertion, a[indices] is the same as a[np.index_exp[indices]] for any array a. However, np.index_exp[indices] can be used anywhere in Python code and returns a tuple of slice objects that can be used in the construction of complex index expressions.

Parameters

maketuple : bool

If True, always returns a tuple.

Notes

You can do all this with slice plus a few special objects, but there's a lot to remember and this version is simpler because it uses the standard array indexing syntax.

Examples

import numpy as np
np.s_[2::2]
np.index_exp[2::2]
✓
np.array([0, 1, 2, 3, 4])[np.s_[2::2]]
✓

See also

s_

Predefined instance without tuple conversion: s_ = IndexExpression(maketuple=False). The index_exp is another predefined instance that always returns a tuple: index_exp = IndexExpression(maketuple=True).

Aliases

  • numpy.lib._index_tricks_impl.IndexExpression