Pythonȫջѧϰ_day003֪ʶµã

2018-10-26 05:29:23À´Ô´£º²©¿ÍÔ° ÔĶÁ ()

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1. »ù´¡Êý¾ÝÀàÐÍ ×ÜÀÀ
2. int
3. bool
4. str
5. forÑ­»·

 

1. »ù´¡Êý¾ÝÀàÐÍ ×ÜÀÀ
 ¡¡ int: ÓÃÓÚ¼ÆË㣬¼ÆÊýµÈ
    str£º'ÕâЩÄÚÈÝ'£¬Óû§ÉÙÁ¿Êý¾ÝµÄ´æ´¢£¬±ãÓÚ²Ù×÷
    bool£ºTrue, False£¬Á½ÖÖ״̬£¬»úÆ÷·´À¡¸øÓû§µÄ¶Ô/´í
    list£º[1, 'k', True, [], (), {}, ...] ´óÁ¿µÄÊý¾Ý£¬¸÷ÖÖÊý¾ÝÀàÐÍ£¬²Ù×÷·½±ã
    tuple£º(1, 'k', True, [], (), {}, ...) Ö»¶ÁÁбí
    dict£º×Öµä. ´óÁ¿µÄ¹ØÁªÐÔÊý¾Ý
        {'name': 'alex', 'name_list': ['˾ͽ', 'ÀîÁ«Ó¢', ...], 'Ì«°×': {'name': 'Ì«°×', 'sex': 'ÄÐ'}}
    set£º¼¯ºÏ. {} ¹Øϵ²âÊÔ. Á½ÖÖ¼¯ºÏÖ®¼äµÄ²¢¼¯ÊÇʲôµÈµÈ.

 

2. int

i = 4
print(i.bit_length())   ²éѯʮ½øÖÆת»¯³É¶þ½øÖÆÕ¼ÓõÄ×îСλÊý
½á¹û£º
3

Ê®½øÖÆ             ¶þ½øÖÆ
   1              0000 0001
   2              0000 0010
   3              0000 0011
   4              0000 0100

 

3. bool

Êý¾ÝÀàÐÍÖ®¼äµÄת»¯
int <--> str     str(int); int(str)       ******
int <--> bool    ·Ç0ΪTrue; 0ΪFalse     True --> 1; False --> 0
str --> bool    ''(¿Õ×Ö·û´®) --> False; ·Ç¿Õ --> True
    name = input('>>>')
    if name:
        print(666)
    else:
        print('ÎÞÄÚÈÝ')
        
bool --> str    ûɶÒâÒå

 

4. str


¶Ô×Ö·û´®µÄÏÂÃæÕâÁ½²¿·Ö²Ù×÷£¬ÐγɵĶ¼ÊÇÒ»¸öеÄ×Ö·û´®£¬ÓëÔ­À´µÄ×Ö·û´®Ã»ÓйØϵ


µÚÒ»²¿·Ö£ºË÷Òý¡¢ÇÐƬ¡¢²½³¤


- °´ÕÕË÷ÒýÈ¡Öµ£¬È¡³öÀ´µÄ¶¼ÊÇÒ»¸ö×Ö·ûÐγɵÄ×Ö·û´®
s1 = 'Python1ÆÚ_ÆïÊ¿¼Æ»®'
s2 = s1[0]
print(s2)       P
print(type(s2))     <class 'str'>

s3 = s1[2]
print(s3)       t

s4 = s1[-1]
print(s4)       »®

s5 = s1[-2]
print(s5)       ¼Æ


- °´ÕÕÇÐƬȡֵ, ¹ËÍ·²»¹Ëβ
s6 = s1[0:6]
print(s6)       Python

s61 = s1[:6]
print(s61)      Python

s7 = s1[1:7]
print(s7)       ython1

s8 = s1[6:-1]
print(s8)       1ÆÚ_ÆïÊ¿¼Æ

s81 = s1[6:]
print(s81)      1ÆÚ_ÆïÊ¿¼Æ»®


- °´ÕÕÇÐƬ+²½³¤
s1 = 'Python1ÆÚ_ÆïÊ¿¼Æ»®'

s9 = s1[:5:2]
print(s9)       Pto

s91 = s1[1::2]
print(s91)      yhnÆÚÆï¼Æ
Èç¹ûÏëµ¹ÐòÈ¡Öµ£¬¼ÓÒ»¸ö·´Ïò²½³¤(¸ººÅ)
s10 = s1[-1:-5:-1]
print(s10)      »®¼ÆÊ¿Æï

s11 = s1[-1:-6:-2]
print(s11)      »®Ê¿_


µÚ¶þ²¿·Ö£º×Ö·û´®µÄ³£Ó÷½·¨
name = 'old boy'

print(name.capitalize())    Old boy;Ê××Öĸ´óд    ***

print(name.title())         Old Boy
s1 = 'alex wusir*taibai6nvshen'
print(s1.title())   ·Ç×Öĸ¸ô¿ªµÄÿ¸ö²¿·ÖµÄÊ××Öĸ´óд    **
center: ×Ö·û´®¾ÓÖУ¬Ç°ºóÌî³ä×Ô¶¨ÒåµÄ×Ö·û  **
print(name.center(20, '*'))     ******old boy*******
upper(È«²¿´óд); lower(È«²¿Ð¡Ð´)        ******
print(name.upper())     OLD BOY
print(name.lower())     old boy
Ó¦ÓþÙÀý£º
username = input('ÇëÊäÈëÓû§Ãû£º')
code = 'ADfeR'.lower()
your_code = input('ÇëÊäÈëÑéÖ¤Â룺').lower()
if username == 'alex' and code == your_code:
    print('µÇ¼³É¹¦')

name = 'old boy'

startswith: ÅжÏÒÔʲôΪ¿ªÍ·    *****
print(name.startswith('ol'))     True
ÅжϵÚ5¸öλÖÃÖ®ºóµÄ×Ö·û´®ÒÔʲôΪ¿ªÍ·
print(name.startswith('b', 4))  True
ÅжϵÚ2¸öλÖõ½µÚ5¸öλÖõÄ×Ö·û´®ÒÔʲôΪ¿ªÍ·
print(name.startswith('ld', 1, 5))      True

endswith: ÅжÏÒÔʲôΪ½áβ      *****
ÓëstartswithÓ÷¨Ò»ÖÂ
print(name.endswith('o'))       False

swapcase: ´óСдת»»     **
name = 'oLd boY'
print(name.swapcase())      OlD BOy


find(*****): ͨ¹ýÔªËØÕÒË÷Òý, ÕÒµ½µÚÒ»¸öÔªËؾͷµ»ØÆäË÷ÒýÖµ£¬Ã»ÓдËÔªËØÔò·µ»Ø-1   *****
print(name.find('d'))       2
print(name.find('Ld'))      1
print(name.find('w'))       -1
print(name.find('o', 1, -1))    5; findÒ²¿ÉÒÔÉèÖÃ×Ö·û´®µÄ¿ªÊ¼ºÍ½áÊøλÖÃ

index(*****): ͨ¹ýÔªËØÕÒË÷Òý, ÕÒµ½µÚÒ»¸öÔªËؾͷµ»ØÆäË÷ÒýÖµ£¬Ã»ÓдËÔªËØÔò±¨´í
print(name.index('w'))      ±¨´í


strip(*****): ĬÈÏÈ¥³ý×Ö·û´®Ç°ºóµÄ¿Õ¸ñ£¬»»Ðзû(\n)£¬ÖƱí·û(\t)
name = '\told boy '
print(name.strip())
½á¹û£º
old boy

strip£ºÖ¸¶¨È¥³ýµÄ×Ö·û
name1 = '*alex**'
print(name1.strip('*'))      alex

name2 = 'weralexqwe'
print(name2.strip('erw'))       alexq
Ó¦ÓþÙÀý£º
username = input('ÇëÊäÈëÓû§Ãû£º').strip()
if username == 'alex':
    print('µÇ¼³É¹¦')
lstrip: È¥³ýÇ°ÃæµÄ¿Õ¸ñ
rstrip: È¥³ýºóÃæµÄ¿Õ¸ñ

split: ½«×Ö·û´®·Ö¸î³ÉÁбí(str --> list); ĬÈÏ°´ÕÕ¿Õ¸ñ·Ö¸î
s1 = 'alex wusir taibai'
l1 = s1.split()
print(l1)       ['alex', 'wusir', 'taibai']

s2 = 'alex,wusir taibai'
l2 = s2.split(',')
print(l2)       ['alex', 'wusir taibai']
×¢ÒâÕâÈý¸öµÄÇø±ð
s3 = ' alex wusir taibai'
print(s3.split())       ['alex', 'wusir', 'taibai']

s31 = ' alex wusir taibai'
print(s31.split(' '))   ['', 'alex', 'wusir', 'taibai']

s4 = ',alex,wusir,taibai'
print(s4.split(','))    ['', 'alex', 'wusir', 'taibai']
ÉèÖÃsplitµÄ·Ö¸î´ÎÊý
s5 = 'alexlwle'
print(s5.split('l', 1))     ['a', 'exlwle']

print(s5.rsplit('l'))


join(**********): ×Ô¶¨ÖÆÁ¬½Ó·û£¬½«¿Éµü´ú¶ÔÏóÖеÄÔªËØÁ¬½ÓÆðÀ´
str1 = 'alex'
s2 = '*'.join(str1)
print(s2)       a*l*e*x


replace(*****): Ìæ»»
str2 = 'alex ÊÇ´´Ê¼ÈË£¬alexºÜÅ£±Æ£¬alex...'
s3 = str2.replace('alex', 'SB')
print(s3)       SB ÊÇ´´Ê¼ÈË£¬SBºÜÅ£±Æ£¬SB...
¿ÉÒÔÉèÖÃÌæ»»´ÎÊý£¬µ«ÊÇÖ»ÄÜ´ÓÇ°Íùºó¿ªÊ¼Ìæ»»
str2 = 'alex ÊÇ´´Ê¼ÈË£¬alexºÜÅ£±Æ£¬alex...'
s3 = str2.replace('alex', 'SB', 1)
print(s3)       SB ÊÇ´´Ê¼ÈË£¬alexºÜÅ£±Æ£¬alex...

¸ñʽ»¯Êä³ö: format
ÈýÖÖ·½Ê½
µÚÒ»ÖÖ£º
s1 = 'ÎÒ½Ð{}, ½ñÄê{}, ÐÔ±ð{}'.format('Ì«°×', '28', 'ÄÐ')
print(s1)       ÎÒ½ÐÌ«°×, ½ñÄê28, ÐÔ±ðÄÐ
µÚ¶þÖÖ£º
s2 = 'ÎÒ½Ð{0}, ½ñÄê{1}, ÐÔ±ð{2}, ÎÒ»¹ÊǽÐ{0}'.format('Ì«°×', '28', 'ÄÐ')
print(s2)       ÎÒ½ÐÌ«°×, ½ñÄê28, ÐÔ±ðÄÐ, ÎÒ»¹ÊǽÐÌ«°×
µÚÈýÖÖ£º
s3 = 'ÎÒ½Ð{name}, ½ñÄê{age}, ÐÔ±ð{sex}, ÎÒ»¹ÊǽÐ{name}'.format(age = '28', name = 'Ì«°×', sex = 'ÄÐ')
print(s3)       ÎÒ½ÐÌ«°×, ½ñÄê28, ÐÔ±ðÄÐ, ÎÒ»¹ÊǽÐÌ«°×


is ϵÁÐ
name = 'taibai123'
print(name.isalnum())   True; ÅжÏnameÊÇ·ñÒÔ×Öĸ»òÕßÊý×Ö×é³É
print(name.isdigit())   False; ÅжÏnameÊÇ·ñÈ«²¿ÒÔÊý×Ö×é³É
print(name.isalpha())   False; ÅжÏnameÊÇ·ñÈ«²¿ÒÔ×Öĸ×é³É

¹«¹²·½·¨
count: ¼ÆÊý£¬¼ÆËã¸ø¶¨×Ö·û³öÏÖ¼¸´Î£¬¿ÉÒÔ½øÐÐÇÐƬ
name = 'alex'
print(name.count('a'))      1

len: ¼ÆËã×Ö·û´®Óж೤£¬¾ÍÊÇÔªËصĸöÊý
print(len(name))        4

 

5. forÑ­»·

ÏÈÓÃwhileÑ­»·´òӡÿ¸öÔªËØ
s1 = 'sdkjasgfjgsafkj'
index = 0
while index < len(s1):
    print(s1[index])
    index += 1
Èç¹û¶ÔÒ»¸öÊý¾ÝÀàÐͽøÐÐÑ­»·»òÕßÊÇÒ»¸öÓÐÏÞÑ­»·µÄʱºò£¬ÍùÍùÒªÓõ½forÑ­»·
for i in s1:    for ±äÁ¿ in iterable(¿Éµü´ú¶ÔÏó)
    print(i)
    
for i in s1:    for Ñ­»·µÄ´ÎÊýÊǺͿɵü´ú¶ÔÏóµÄÔªËصĸöÊýÓйØ
    print(s1)

 

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