davrot/pytutorial
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

Update README.md

Browse source 
Signed-off-by: David Rotermund <54365609+davrot@users.noreply.github.com>
This commit is contained in:
David Rotermund 2023-12-15 10:55:01 +01:00 committed by GitHub
parent ec7204e758
commit dd74e2efcd
No known key found for this signature in database
GPG key ID: 4AEE18F83AFDEB23
1 changed files with 44 additions and 0 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

44
numpy/ndarray/README.md
View file

@ -704,6 +704,50 @@ Output:
[2]]
```
## [numpy.ndarray.std](https://numpy.org/doc/stable/reference/generated/numpy.ndarray.std.html) and [numpy.ndarray.var](https://numpy.org/doc/stable/reference/generated/numpy.ndarray.var.html)
```python
ndarray.std(axis=None, dtype=None, out=None, ddof=0, keepdims=False, *, where=True)
```
> Returns the standard deviation of the array elements along given axis.
```python
ndarray.var(axis=None, dtype=None, out=None, ddof=0, keepdims=False, *, where=True)
```
> Returns the variance of the array elements, along given axis.
```python
import numpy as np
rng = np.random.default_rng()
A = rng.random((2, 3))
print(A)
print()
print(A.var()) # -> 0.15743358550255018
print(A.var(axis=0)) # -> [0.19429192 0.15604444 0.00441136]
print(A.var(axis=0).shape) # -> (3,)
print(A.var(axis=1)) # -> [0.18135622 0.00196335]
print(A.var(axis=1).shape) # -> (2,)
print(A.var(axis=0, keepdims=True)) # -> [[0.19429192 0.15604444 0.00441136]]
print(A.var(axis=0, keepdims=True).shape) # -> (1, 3)
print(A.var(axis=1, keepdims=True))
print(A.var(axis=0, keepdims=True).shape) # -> (1, 3)
```
Output:
```python
[[0.9804056 0.82416017 0.00909 ]
[0.09883446 0.03411095 0.1419262 ]]
[[0.18135622]
[0.00196335]]
```
## [Array methods](https://numpy.org/doc/stable/reference/arrays.ndarray.html#array-methods)
### [Array conversion](https://numpy.org/doc/stable/reference/arrays.ndarray.html#array-conversion)