python实现七种列表去重方法
#encoding=utf-8
import time
time_start=time.time()
print u"列表去重的七种方法"
print u"第一种测试方法"
repeat_list=[1,2,4,1,5,1,2,5]
result=[]
for i in repeat_list:
if i not in result:
result.append(i)
print u"第一种去重结果: ",result
print u"第二种测试方法"
repeat_list=[1,2,4,1,5,1,2,5]
result={}
print u"第二种去重结果: ",list(result.fromkeys(repeat_list))
print u"第三种测试方法"
repeat_list=[1,2,4,1,5,1,2,5]
print u"第三种去重结果: ",list(set(repeat_list))
print u"第四种测试方法"
repeat_list=[1,2,4,1,5,1,2,5]
import itertools
def test_groupby(x):
if x==1:
print "lower"
elif x>1 and x<4:
print "middle"
elif x>=4:
print "higher"
import time
time_start=time.time()
print u"列表去重的七种方法"
print u"第一种测试方法"
repeat_list=[1,2,4,1,5,1,2,5]
result=[]
for i in repeat_list:
if i not in result:
result.append(i)
print u"第一种去重结果: ",result
print u"第二种测试方法"
repeat_list=[1,2,4,1,5,1,2,5]
result={}
print u"第二种去重结果: ",list(result.fromkeys(repeat_list))
print u"第三种测试方法"
repeat_list=[1,2,4,1,5,1,2,5]
print u"第三种去重结果: ",list(set(repeat_list))
print u"第四种测试方法"
repeat_list=[1,2,4,1,5,1,2,5]
import itertools
def test_groupby(x):
if x==1:
print "lower"
elif x>1 and x<4:
print "middle"
elif x>=4:
print "higher"
repeat_list=sorted(repeat_list)
data=itertools.groupby(repeat_list,key=test_groupby)
for i,j in data:
print list(j)
data=itertools.groupby(repeat_list)
result=[]
for i,j in data:
result.append(i)
print u"第四种去重结果: ",result
print u"第五种测试方法"
repeat_list=[1,2,4,1,5,1,2,5]
for i in [j for j in repeat_list if repeat_list.count(i)>1]:
for x in range(repeat_list.count(i)-1):
repeat_list.remove(i)
print u"第五种去重结果: ",repeat_list
print u"第六种测试方法"
repeat_list=[1,2,4,1,5,1,2,5]
i=0
while i<=len(repeat_list)-1:
if repeat_list.count(repeat_list[i])>1:
repeat_list.pop(i)
else:
i+=1
print u"第六种去重结果: ",repeat_list
print u"第七种测试方法"
repeat_list=[1,2,4,1,5,1,2,5]
func=lambda x,y:x if y in x else x + [y]
print u"第七种去重结果: ",reduce(func,[[],]+repeat_list)
print "_"*20
print u"去重程序耗时%f" % (time.time()-time_start)
print "_"*20
time.sleep(3)
data=itertools.groupby(repeat_list,key=test_groupby)
for i,j in data:
print list(j)
data=itertools.groupby(repeat_list)
result=[]
for i,j in data:
result.append(i)
print u"第四种去重结果: ",result
print u"第五种测试方法"
repeat_list=[1,2,4,1,5,1,2,5]
for i in [j for j in repeat_list if repeat_list.count(i)>1]:
for x in range(repeat_list.count(i)-1):
repeat_list.remove(i)
print u"第五种去重结果: ",repeat_list
print u"第六种测试方法"
repeat_list=[1,2,4,1,5,1,2,5]
i=0
while i<=len(repeat_list)-1:
if repeat_list.count(repeat_list[i])>1:
repeat_list.pop(i)
else:
i+=1
print u"第六种去重结果: ",repeat_list
print u"第七种测试方法"
repeat_list=[1,2,4,1,5,1,2,5]
func=lambda x,y:x if y in x else x + [y]
print u"第七种去重结果: ",reduce(func,[[],]+repeat_list)
print "_"*20
print u"去重程序耗时%f" % (time.time()-time_start)
print "_"*20
time.sleep(3)