NumPy的数组

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PS C:Usersa-xiaobodou> python -m pip install --upgrade pip
C:msys64mingw64binpython.exe: No module named pip
PS C:Usersa-xiaobodou> python -m pip install numpy
C:msys64mingw64binpython.exe: No module named pip
PS C:Usersa-xiaobodou> python3 -m pip install numpy
C:msys64mingw64binpython3.exe: No module named pip
PS C:Usersa-xiaobodou> pip install numpy
Requirement already satisfied: numpy in c:usersa-xiaobodouappdatalocalprogramspythonpython310libsite-packages (1.22.3)
PS C:Usersa-xiaobodou> python -i
Python 3.9.11 (main, Mar 18 2022, 16:54:01)  [GCC 11.2.0 64 bit (AMD64)] on win32
Type "help", "copyright", "credits" or "license" for more information.
>>> from numpy import *
Traceback (most recent call last):
  File "", line 1, in 
ModuleNotFoundError: No module named 'numpy'
>>> eye(4)
Traceback (most recent call last):
  File "", line 1, in 
NameError: name 'eye' is not defined
>>>

不明白，为什么在命令提示符出现ModuleNotFoundError：No mudule namy 'numpy'

Python 3.10.2 (tags/v3.10.2:a58ebcc, Jan 17 2022, 14:12:15) [MSC v.1929 64 bit (AMD64)] on win32
Type "help", "copyright", "credits" or "license" for more information.
>>> from numpy import *
>>> eye(4)
array([[1., 0., 0., 0.],
       [0., 1., 0., 0.],
       [0., 0., 1., 0.],
       [0., 0., 0., 1.]])
>>>

Python 3.10.2 (tags/v3.10.2:a58ebcc, Jan 17 2022, 14:12:15) [MSC v.1929 64 bit (AMD64)] on win32
Type "help", "copyright", "credits" or "license" for more information.
>>> import numpy as np
>>> my_array=np.array([1,2,3,4,5])
>>> print my_array
  File "", line 1
    print my_array
    ^^^^^^^^^^^^^^
SyntaxError: Missing parentheses in call to 'print'. Did you mean print(...)?
>>> print my_array
  File "", line 1
    print my_array
    ^^^^^^^^^^^^^^
SyntaxError: Missing parentheses in call to 'print'. Did you mean print(...)?
>>> print(my_array)
[1 2 3 4 5]
>>> print(my_array.shape)
(5,)
>>> print(my_array[0])
1
>>> my_array[0]=-1
>>> print(my_array[0])
-1
>>> print(my_array)
[-1  2  3  4  5]
>>> my_new_array=np.zeros((5))
>>> print(my_random_array)
Traceback (most recent call last):
  File "", line 1, in 
NameError: name 'my_random_array' is not defined. Did you mean: 'my_new_array'?
>>> print(my_new_array)
[0. 0. 0. 0. 0.]
>>> my_random_array=np.radom.radom((5))
Traceback (most recent call last):
  File "", line 1, in 
  File "C:Usersa-xiaobodouAppDataLocalProgramsPythonPython310libsite-packagesnumpy__init__.py", line 315, in __getattr__
    raise AttributeError("module {!r} has no attribute "
AttributeError: module 'numpy' has no attribute 'radom'. Did you mean: 'random'?
>>> my_random_array=np.random.radom((5))
Traceback (most recent call last):
  File "", line 1, in 
AttributeError: module 'numpy.random' has no attribute 'radom'. Did you mean: 'random'?
>>> my_random_array=np.random.random((5))
>>> print(my_random_array)
[0.25351566 0.7168677  0.13383434 0.56201388 0.80009886]
>>> my_2d_array=np.zeros((2,3)) print(my_2d_array)
  File "", line 1
    my_2d_array=np.zeros((2,3)) print(my_2d_array)
                                ^^^^^
SyntaxError: invalid syntax
>>> my_2d_array=np.zeros((2,3))
>>> print(my_ad_array)
Traceback (most recent call last):
  File "", line 1, in 
NameError: name 'my_ad_array' is not defined. Did you mean: 'my_2d_array'?
>>> print(my_2d_array)
[[0. 0. 0.]
 [0. 0. 0.]]
>>> my_ad_array_new=np.ones((2,4))
>>> print(my_2d_array_new)
Traceback (most recent call last):
  File "", line 1, in 
NameError: name 'my_2d_array_new' is not defined. Did you mean: 'my_ad_array_new'?
>>> print(my_ad_array_new)
[[1. 1. 1. 1.]
 [1. 1. 1. 1.]]
>>> my_array=np.array([4,5],[6,1])
Traceback (most recent call last):
  File "", line 1, in 
TypeError: Field elements must be 2- or 3-tuples, got '6'
>>> my_array=np.array([[4,5],[6,1]])
>>> print(my_array[0][1])
5
>>> print(my_array)
[[4 5]
 [6 1]]
>>> print(my_array.shape)
(2, 2)
>>> my_array_column_2=my_array[:,1]
>>> print(my_array_colum_2)
Traceback (most recent call last):
  File "", line 1, in 
NameError: name 'my_array_colum_2' is not defined. Did you mean: 'my_array_column_2'?
>>> print(my_array_column_2)
[5 1]
>>>

Python 3.10.2 (tags/v3.10.2:a58ebcc, Jan 17 2022, 14:12:15) [MSC v.1929 64 bit (AMD64)] on win32
Type "help", "copyright", "credits" or "license" for more information.
>>> import numpy as np
>>> a=np.array([[1.0,2.0],[3.0,4.0]])
>>> b=np.array([[5.0,6.0],[7.0,8.0]])
>>> sum=a+b
>>> difference=a-b
>>> product=a*b
>>> quotient=a/b
>>> print('Sum=n',sum)
Sum=
 [[ 6.  8.]
 [10. 12.]]
>>> print('Difference =n',difference)
Difference =
 [[-4. -4.]
 [-4. -4.]]
>>> print('Product =n',product)
Product =
 [[ 5. 12.]
 [21. 32.]]
>>> print('Quotient =n', quotient)
Quotient =
 [[0.2        0.33333333]
 [0.42857143 0.5       ]]
>>>
>>> print(a)
[[1. 2.]
 [3. 4.]]
>>> print(b)
[[5. 6.]
 [7. 8.]]
>>>
>>> matrix_product=a.dot(b)
>>> print("Matrix Product = ",matrix_product)
Matrix Product =  [[19. 22.]
 [43. 50.]]
>>>