Python3 中有六个标准的数据类型:
- Number(数字)
- String(字符串)
- List(列表)
- Tuple(元组)
- Set(集合)
- Dictionary(字典)
import numpy as np
# number string list tuple dict set
# number: int(x) float(y) complex(x) complex(x,y) 实数部分为x,虚数部分为y
arr = np.array([2, 3, 5, 8]) # 1维数组
print(arr) # [2 3 5 8]
print(type(arr)) # <class 'numpy.ndarray'>
print(arr.shape) # (4,)
print(arr.size) # 4
mat = np.array([[1, 2, 3], [4, 5, 6]]) # 2维数组
print(mat) # [[0. 0. 0.] [0. 0. 0.]]
print(mat.shape) # (2, 3)
print(mat.size) # 6
print(type(mat)) # <class 'numpy.ndarray'>
str1 = 'Hello World!' # str ''或“”
print(str1) # Hello World!
print(type(str1)) # <class 'str'>
print(len(str1)) # 12
li = [1, 2, 3, 4] # list 元素可以修改 []
print(li) # [1, 2, 3, 4]
print(type(li)) # <class 'list'>
print(len(li)) # 4
set1 = {8, 2, 3, 5, 8} # set 无序的不重复元素序列 {}
print(set1) # {8, 2, 3, 5}
print(type(set1)) # <class 'set'>
print(len(set1)) # 4
tup = (1, 'a', 'food', 23) # tuple 元素不可以修改 ()
print(tup) # (1, 'a', 'food', 23)
print(type(tup)) # <class 'tuple'>
print(len(tup)) # 4
dict1 = {'name': 'David', 'age': 30, 'sex': 'male'} # dict 可存储任意类型对象 {:}
print(dict1) # {'name': 'David', 'age': 30, 'sex': 'male'}
print(type(dict1)) # <class 'dict'>
print(len(dict1)) # 3