【Python基础】--变量和字符串/猜数字/range()/Isinstance/list[]/tupple()
2016-11-02
>>> name = 'wuyq' >>> name 'wuyq' >>> print(name) wuyq >>> print('name = %s', % name) SyntaxError: invalid syntax >>> print('name = %s' % name) name = wuyq >>> print('name = %s', name) name = %s wuyq >>>
>>> first = 3 >>> second = 5 >>> third = first + second >>> third 8 >>> 3+4 7 >>> '2'+'4' '24' >>> first 3 >>> str1 = 'Let\'s go!' >>> str1 "Let's go!" >>> str2 = "c:\\day01" >>> str2 'c:\\day01' >>> print(str2) c:\day01 >>> str2 = 'c:\now' >>> str2 'c:\now' >>> print(str2) c: ow >>> str2 = r'c:\now' >>> str2 'c:\\now' >>> print(str2) c:\now >>>
import random secret = random.randint(1, 10) temp = input("inut guess num[1-10]:") guess = int(temp) while guess != secret: if guess == secret: print(" wa, cai zhong le ") break else: if guess > secret: print("da le da le ") else: print("xiao le") temp = input("inut guess num[1-10]:") guess = int(temp) print("game over ")
range(a, b)返回的是所有大于等于a,小于b的整数构成的数组
-比如range(2, 3)返回数组[2],range(2, 4)返回数组[2, 3]
-另外,range()也可以接收1个和3个参数
1个参数代表返回0到这个参数(不包括该参数)之间的值,如range(3) = [0, 1, 2]
3个参数中的第三个代表步长,即间隔, 如range(1, 8, 2) = [1, 3, 5, 7]
>>> a = 'wuyq' >>> isinstance(str, a) Traceback (most recent call last): File "<pyshell#170>", line 1, in <module> isinstance(str, a) TypeError: isinstance() arg 2 must be a type or tuple of types >>> isinstance(a, str) True >>>
>>> member = ['wuyq', 'zhang', 'wang', 'cheng'] >>> member ['wuyq', 'zhang', 'wang', 'cheng'] >>> number = [1, 2, 3, 4] >>> number [1, 2, 3, 4] >>> mix = [12, 3.12, 'wuyq', [1, 3, 4], 'haha'] >>> mix [12, 3.12, 'wuyq', [1, 3, 4], 'haha'] >>> mix[3] [1, 3, 4] >>> empty = [] >>> empty [] >>> member.append('nihao') >>> member ['wuyq', 'zhang', 'wang', 'cheng', 'nihao'] >>> len(member) 5 >>> member.extend(['one', 'two']) >>> len(member) 7 >>> member.insert(1, 'second') >>> member ['wuyq', 'second', 'zhang', 'wang', 'cheng', 'nihao', 'one', 'two'] >>> len(member) 8 >>>
>>> member = ['wuyq', 'zhang', 'wang'] >>> member ['wuyq', 'zhang', 'wang'] >>> member.remove('zhang') >>> member ['wuyq', 'wang'] >>> del member[1] >>> member ['wuyq'] >>>
>>> member = ['wuyq', 'zhang', 'wang', 'liu'] >>> member.pop() 'liu' >>> member ['wuyq', 'zhang', 'wang'] >>> name = member.pop() >>> name 'wang' >>> member ['wuyq', 'zhang'] >>> member.pop(1) 'zhang' >>> member ['wuyq'] >>>
>>> member = ['wuyq', 'zhang', 'wang', 'liu', 'haha'] >>> member[1:3] ['zhang', 'wang'] >>> member[1:-2] ['zhang', 'wang'] >>> member ['wuyq', 'zhang', 'wang', 'liu', 'haha'] >>> member2 = member[:] >>> member2 ['wuyq', 'zhang', 'wang', 'liu', 'haha'] >>>
>>> number = [1, 3, 4, 5, 12 , 1, 3, 4] >>> number.count(3) 2 >>> number.index(4) 2 >>> number.index(1, 2, 7) 5 >>> number.reverse() >>> number [4, 3, 1, 12, 5, 4, 3, 1] >>> number.sort() >>> number [1, 1, 3, 3, 4, 4, 5, 12] >>> number2 = number[:] >>> number2 [1, 1, 3, 3, 4, 4, 5, 12] >>> number3 = number >>> number2 [1, 1, 3, 3, 4, 4, 5, 12] >>> number3 [1, 1, 3, 3, 4, 4, 5, 12] >>> number.reverse() >>> number [12, 5, 4, 4, 3, 3, 1, 1] >>> number2 [1, 1, 3, 3, 4, 4, 5, 12] >>> number3 [12, 5, 4, 4, 3, 3, 1, 1] >>>
元组是另一个数据类型,类似于List(列表)。
元组用"()"标识。内部元素用逗号隔开。但是元组不能二次赋值,相当于只读列表。
>>> tuple1 = (1, 2, 3, 4, 5, 6, 7, 8) >>> tuple1 (1, 2, 3, 4, 5, 6, 7, 8) >>> tuple1[2] 3 >>> tuple1[2:5] (3, 4, 5) >>> tuple2 = tuple1 >>> tuple2 (1, 2, 3, 4, 5, 6, 7, 8) >>> tuple2[3] = 12 Traceback (most recent call last): File "<pyshell#138>", line 1, in <module> tuple2[3] = 12 TypeError: 'tuple' object does not support item assignment >>> tmp = (1) >>> tmp 1 >>> type(tmp) <class 'int'> >>> tmp2 = 2, 3, 4 >>> type(tmp2) <class 'tuple'> >>> list1 = [] >>> type(list1) <class 'list'> >>> tmp3 = () >>> type(tmp3) <class 'tuple'> >>> tmp4 = (2, ) >>> type(tmp4) <class 'tuple'> >>>
>>> tmp = ('wuyq', 'zhang', 'wuang', ) >>> tmp = ('wuyq', 'zhang', 'wuang', 'xiao', 'python', 'cpp') >>> tmp ('wuyq', 'zhang', 'wuang', 'xiao', 'python', 'cpp') >>> tmp = tmp[:2] + 'java' + tmp[2:] Traceback (most recent call last): File "<pyshell#153>", line 1, in <module> tmp = tmp[:2] + 'java' + tmp[2:] TypeError: can only concatenate tuple (not "str") to tuple >>> tmp = tmp[:2] + ('java',) + tmp[2:] >>> tmp ('wuyq', 'zhang', 'java', 'wuang', 'xiao', 'python', 'cpp') >>>