Insert values along the given axis before the given indices.
Input array.
Object that defines the index or indices before which values is inserted.
Changed in version 2.1.2: Boolean indices are now treated as a mask of elements to insert, rather than being cast to the integers 0 and 1.
Support for multiple insertions when obj is a single scalar or a sequence with one element (similar to calling insert multiple times).
Values to insert into arr. If the type of values is different from that of arr, values is converted to the type of arr. values should be shaped so that arr[...,obj,...] = values
is legal.
Axis along which to insert values. If axis is None then arr is flattened first.
A copy of arr with values inserted. Note that insert
does not occur in-place: a new array is returned. If axis is None, out is a flattened array.
See also
append
Append elements at the end of an array.
concatenate
Join a sequence of arrays along an existing axis.
delete
Delete elements from an array.
Notes
Note that for higher dimensional inserts obj=0
behaves very different from obj=[0]
just like arr[:,0,:] = values
is different from arr[:,[0],:] = values
. This is because of the difference between basic and advanced indexing.
Examples
>>> import numpy as np >>> a = np.arange(6).reshape(3, 2) >>> a array([[0, 1], [2, 3], [4, 5]]) >>> np.insert(a, 1, 6) array([0, 6, 1, 2, 3, 4, 5]) >>> np.insert(a, 1, 6, axis=1) array([[0, 6, 1], [2, 6, 3], [4, 6, 5]])
Difference between sequence and scalars, showing how obj=[1]
behaves different from obj=1
:
>>> np.insert(a, [1], [[7],[8],[9]], axis=1) array([[0, 7, 1], [2, 8, 3], [4, 9, 5]]) >>> np.insert(a, 1, [[7],[8],[9]], axis=1) array([[0, 7, 8, 9, 1], [2, 7, 8, 9, 3], [4, 7, 8, 9, 5]]) >>> np.array_equal(np.insert(a, 1, [7, 8, 9], axis=1), ... np.insert(a, [1], [[7],[8],[9]], axis=1)) True
>>> b = a.flatten() >>> b array([0, 1, 2, 3, 4, 5]) >>> np.insert(b, [2, 2], [6, 7]) array([0, 1, 6, 7, 2, 3, 4, 5])
>>> np.insert(b, slice(2, 4), [7, 8]) array([0, 1, 7, 2, 8, 3, 4, 5])
>>> np.insert(b, [2, 2], [7.13, False]) # type casting array([0, 1, 7, 0, 2, 3, 4, 5])
>>> x = np.arange(8).reshape(2, 4) >>> idx = (1, 3) >>> np.insert(x, idx, 999, axis=1) array([[ 0, 999, 1, 2, 999, 3], [ 4, 999, 5, 6, 999, 7]])
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