python中内置函数和json、pickle的数据序列化代码实例

内置函数

map

res = map(lambda n:n**n, range(10))
res1 = [lambda i:i*2 for i in range(10)]
for i in res1:
    print(i)

reduce

import functools
res = functools.reduce(lambda  x, y:x+y, range(10))
print(res)

对字典排序的函数

#对字典排序
a = {6:2, 3:12, 99:11, -1:2}
print(sorted(a.items()))
#指定排序方式
print(sorted(a.items(), key = lambda x:x[1]))

将两个数组拼成一个数组

a = [1,2,3,4]
b = ['a', 'b', 'c', 'd']
for i in zip(a,b):
    print(i)

json和pickle数据序列化

# info = {
#     'name':'dancheng',
#     'age':20
# }
# f = open('test.text', 'w')
# f.write(str(info))                  #将json对象变成字符串
# f.close()

# f = open('test.text','r')
# data = eval(f.read())             #将字符串转成json对象
# f.close()
# print(data['name'])

调用json包

info = {
    'name':'dancheng1',
    'age':20,
    'func':sayhi('dancheng')
}
f = open('test.text', 'w')
f.write(json.dumps({1:2}))
f.close()

调用pickle包

import pickle
info = {
    'name':'dancheng1',
    'age':20,
}
f = open('test.text', 'wb')
f.write(pickle.dumps(info))
f.close()
import pickle
f = open('test.text', 'rb')
data = pickle.loads(f.read())
f.close()
print(data)