在上一篇文章中我们使用推导列表对代码进行了简化，并得到了对应的结果，我们首先来看一下上篇文章中得到的结果，如下：
>>> ================================ RESTART ================================ >>> [‘2.01‘, ‘2.01‘, ‘2.22‘, ‘2.34‘, ‘2.34‘, ‘2.45‘, ‘3.01‘, ‘3.10‘, ‘3.21‘] [‘2.11‘, ‘2.11‘, ‘2.23‘, ‘2.23‘, ‘2.59‘, ‘3.10‘, ‘3.10‘, ‘3.21‘, ‘3.21‘] [‘2.22‘, ‘2.38‘, ‘2.49‘, ‘3.01‘, ‘3.01‘, ‘3.02‘, ‘3.02‘, ‘3.02‘, ‘3.22‘] [‘2.18‘, ‘2.25‘, ‘2.39‘, ‘2.54‘, ‘2.55‘, ‘2.55‘, ‘2.55‘, ‘2.58‘, ‘2.58‘]
我们可以看到，这结果中存在一些重复的元素，这个我们得想一个办法把他给去除。
def sanitize(time_string):
if ‘-‘ in time_string:
splitter=‘-‘
elif ‘:‘ in time_string:
splitter=‘:‘
else:
return(time_string)
(mins,secs)=time_string.split(splitter)
return(mins+‘.‘+secs)
with open(‘james.txt‘) as jaf:
data=jaf.readline()
james=data.strip().split(‘,‘)
with open(‘julie.txt‘) as juf:
data=juf.readline()
julie=data.strip().split(‘,‘)
with open(‘mikey.txt‘) as mif:
data=mif.readline()
mikey=data.strip().split(‘,‘)
with open(‘sarah.txt‘) as saf:
data=saf.readline()
sarah=data.strip().split(‘,‘)
james=sorted([sanitize(t) for t in james])
julie=sorted([sanitize(t) for t in julie])
mikey=sorted([sanitize(t) for t in mikey])
sarah=sorted([sanitize(t) for t in sarah])
unique_james=[]
for each in james:
if each not in unique_james:
unique_james.append(each)
unique_julie=[]
for each in julie:
if each not in unique_julie:
unique_julie.append(each)
unique_mikey=[]
for each in mikey:
if each not in unique_mikey:
unique_mikey.append(each)
unique_sarah=[]
for each in sarah:
if each not in unique_sarah:
unique_sarah.append(each)
"""打印四个列表"""
print(unique_james)
print(unique_julie)
print(unique_mikey)
print(unique_sarah)
运行结果如下：>>> ================================ RESTART ================================ >>> [‘2.01‘, ‘2.22‘, ‘2.34‘, ‘2.45‘, ‘3.01‘, ‘3.10‘, ‘3.21‘] [‘2.11‘, ‘2.23‘, ‘2.59‘, ‘3.10‘, ‘3.21‘] [‘2.22‘, ‘2.38‘, ‘2.49‘, ‘3.01‘, ‘3.02‘, ‘3.22‘] [‘2.18‘, ‘2.25‘, ‘2.39‘, ‘2.54‘, ‘2.55‘, ‘2.58‘]
"""打印四个列表""" print(unique_james[0:3]) print(unique_julie[0:3]) print(unique_mikey[0:3]) print(unique_sarah[0:3])结果如下：
>>> ================================ RESTART ================================ >>> [‘2.01‘, ‘2.22‘, ‘2.34‘] [‘2.11‘, ‘2.23‘, ‘2.59‘] [‘2.22‘, ‘2.38‘, ‘2.49‘] [‘2.18‘, ‘2.25‘, ‘2.39‘]
>>> data=[1.1,1.2,1.1,1.5,1.6]
>>> data
[1.1, 1.2, 1.1, 1.5, 1.6]
>>>
>>> data=set(data)
>>> data
{1.1, 1.6, 1.5, 1.2}可以看到，通过set集合已经把data列表中的重复元素给删除了，这里我们要注意一点：通过set函数操作之前，data打印的是以“[]”括起来的，代表是列表，而通过set函数操作以后，data打印的是以“{}”括起来的，代表是集合，这点需要注意一下。def sanitize(time_string):
if ‘-‘ in time_string:
splitter=‘-‘
elif ‘:‘ in time_string:
splitter=‘:‘
else:
return(time_string)
(mins,secs)=time_string.split(splitter)
return(mins+‘.‘+secs)
with open(‘james.txt‘) as jaf:
data=jaf.readline()
james=data.strip().split(‘,‘)
with open(‘julie.txt‘) as juf:
data=juf.readline()
julie=data.strip().split(‘,‘)
with open(‘mikey.txt‘) as mif:
data=mif.readline()
mikey=data.strip().split(‘,‘)
with open(‘sarah.txt‘) as saf:
data=saf.readline()
sarah=data.strip().split(‘,‘)
"""打印四个列表"""
print(sorted(set([sanitize(t) for t in james]))[0:3])
print(sorted(set([sanitize(t) for t in julie]))[0:3])
print(sorted(set([sanitize(t) for t in mikey]))[0:3])
print(sorted(set([sanitize(t) for t in sarah]))[0:3])我们在sorted函数中嵌套set函数将推导列表返回的列表进行去重，然后进行排序，最后输出前面的三个数字，结果如下：>>> ================================ RESTART ================================ >>> [‘2.01‘, ‘2.22‘, ‘2.34‘] [‘2.11‘, ‘2.23‘, ‘2.59‘] [‘2.22‘, ‘2.38‘, ‘2.49‘] [‘2.18‘, ‘2.25‘, ‘2.39‘]运行结果和之前的是一样的。
原文：http://blog.csdn.net/wukongcode/article/details/19293843