1、字典的迭代
1、key值迭代
d = dict(a=1,b=2)
for i in d:
print(i)
for i in d:
print("%s -> %s"
%(i,d[i]))
for key,value
in d.items():
print('%s -> %s' %(key,value))
需要匯入iterable模組
from collections import iterable ##匯入模組
print(isinstance(1,int)) ##判斷1是否是整形
print(isinstance(1,iterable)) ##判斷整形是否可迭代
print(isinstance(1.02,iterable)) ##判斷浮點型是否可迭代
print(isinstance(2e-9,iterable)) ##判斷浮點型是否可迭代
print(isinstance(true,iterable)) ##判斷bool型是否可迭代
print(isinstance('hello',iterable)) ##判斷字串是否可迭代
print(isinstance(,iterable))#判斷字典是否可迭代
for index,value
in enumerate('hello'): ##enumerate 索引，講hello字串的索引值和元素對應列印
print(index,value)
1、傳統方式生成：
import random
ips =
for i in range
(100):
ip = '172.25.254.'+ str(random.randint(1
,255))
print(ips)
print(len(ips))
import random
li = [ '172.25.254.'+str(random.randint(1
,255)) for i in range
(100)]
print(li)
print(len(li))
def
is_div_therr
(num):
return num%3 ==0
print([num**2
for num in range(1,101) if is_div_therr(num)])
1、顯示列表，1-1–只見的所有數求平方
print([i**2
for i in range(1,1011)])
import os
print([ filename for filename in
os.listdir('/var/log') if filename.endswith('.log')])
print([ filename.upper() for filename in
os.listdir('/etc/') if filename.endswith('.conf')])
def
is_prime
(num):
if num<=0:
return
false
elif num==1
and num ==2:
return
true
else:
for i in range(2,num):
if num%i ==0:
return
false
else:
return
true
n = 10
primes_list = [ num for num in range(10) if is_prime(num)]
primes_pair = [(num1,n-num1) for num1 in primes_list if n - num1 in primes_list and num1<= n-num1]
print(len(primes_pair))
print(primes_pair)
print()
d = dict(a=6,b=2,c=3,e=6)
print()
service =
需求1、將字典裡面的key值變大寫
##傳統方法：
new_service = {}
for key,value
in service.items():
new_service[key.upper()] = value
print(new_service)
##字典生成式：
print()
需求2、key值變成大寫， value值在原有基礎上加1
print()
d = dict(a=2,b=10,b=4,e=1,a=1)
print(
li = [ i for i in
range(100) if i%2 ==0]
##生成器
g = (i for i in
range(100) if i%2 ==0)
python3中 g.next方法(), python2.x中g.next()方法；
print(g.__next__())for i in g:
print(i)
g1 = (i for i in range(3))
while
true:
try:
print(g1.__next__())
except stopiteration:
break
fib是值後乙個值是前兩個值相加：1，1，2，3，5，8…
def
fib(num):
# num=5
a, b, count = 0, 1, 1
# a=0, b=1
while count <= num:
yield b # 1
a, b = b, a + b # a=1, b=1
count += 1
g = fib(10) # 如果函式中有yield關鍵字， 返回乙個生成器物件;目前不執行函式內容；
print(g.__next__()) # 當遇到g.__next__方法時， 執行函式, 當遇到yield停止執行; print(g.__next__())時yield後面的值;
print(g.__next__()) # 再次呼叫g.__next__方法時， 從上次停止的地方繼續執行， 遇到yield停止;
g.close() # 關閉生成器
#全部列印
for i in g:
print(i)
def
chat_robot
(): res = ''
while
true:
received = yield res
if'age'
in received or
'年齡'
in received:
res = '年齡保密'
elif
'name'
in received or
'姓名'
in received:
res = '我是小冰'
elif
'money'
in received or
'錢'in received:
res = '沒錢'
else:
res = '我不知道你在說什麼，請換種方法'
defmain
(): robot = chat_robot()
robot.__next__()
while
true:
send_data = input("my>>")
if send_data=='q'
or send_data == 'quit':
print('我也要休息了')
break
robot_data = robot.send(send_data)
print('小冰》',robot_data)
main()
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