Python切片索引用法

print ('a','b','c','d')[2]

sequence="abcdefgh"
print len(sequence)  #显示序列长度
print sequence    #打印完整序列
print sequence[:]
print sequence[2:3]  #切片显示，不指定步长默认为1，指定了步长(这里是setp为2)按照步长进行显示
print sequence[1:6:2]
print sequence[3]   #元素访问
print sequence[0:3]  #从首元素开始访问，访问区间为[0,3)，左开you
print sequence[:3]
print sequence[2:8]  #从第二个元素一直访问到最后一个元素
print sequence[2:]
print sequence[::-1] #从最后一个元素开始访问，逆序访问，可以视为“翻转”操作
print max(sequence)
print min(sequence)
print sequence.index('c')

print sequence*3   #使用重复操作符

print sequence + sequence

str.join(sequence) #方法用于将序列中的元素以指定的字符连接生成一个新的字符串

str = "-";
seq = ("a", "b", "c"); # 字符串序列
print str.join( seq );

a-b-c

list.extend(seq)  #函数用于在列表末尾一次性追加另一个序列中的多个值（用新列表扩展原来的列表）

aList = [123, 'xyz', 'zara', 'abc', 123];
bList = [2009, 'manni'];
aList.extend(bList)
print "Extended List : ", aList ;

Extended List :  [123, 'xyz', 'zara', 'abc', 123, 2009, 'manni']

print ('Faye','Leanna','Daylen')[-100:100]

('Faye', 'Leanna', 'Daylen')

sequence = 'abcdef'
i = -1
for i in range(-1,-len(sequence),-1):
  print sequence[:i]

abcde
abcd
abc
ab
a

sequence = 'abcdef'
for i in [None] + range(-1,-len(sequence),-1):
  print sequence[:i]

abcdef
abcde
abcd
abc
ab
a