python如何链接hadoop，并且使用hadoop的资源，这篇文章介绍了一个简单的案例！
一、python的map/reduce代码
首先认为大家已经对haoop已经有了很多的了解，那么需要建立mapper和reducer，分别代码如下：
1、mapper.py
#!/usr/bin/env python
importsysfor line insys.stdin:
line=line.strip()
words=line.split()for word inwords:print '%s\t%s' %(word, 1)
2、reducer.py
#!/usr/bin/env python
from operator importitemgetterimportsys
current_word=None
current_count=0
word=Nonefor line insys.stdin:
words=line.strip()
word, count= words.split('\t')try:
count=int(count)exceptValueError:continue
if current_word ==word:
current_count+=countelse:ifcurrent_word:print '%s\t%s' %(current_word, current_count)
current_count=count
current_word=wordif current_word ==word:print '%s\t%s' %(current_word, current_count)
建立了两个代码之后，测试一下：
[qiu.li@l-tdata5.tkt.cn6 /export/python]$ echo "I like python hadoop , hadoop very good" | ./mapper.py | sort -k 1,1 | ./reducer.py
,1good1hadoop2I1like1python1very1
二、上传文件
发现没啥问题，那么成功一半了，下面上传几个文件到hadoop做进一步测试。我在线上找了几个文件，命令如下：
wget http://www.gutenberg.org/ebooks/20417.txt.utf-8
wget http://www.gutenberg.org/files/5000/5000-8.txt
wget http://www.gutenberg.org/ebooks/4300.txt.utf-8
查看下载的文件：
[qiu.li@l-tdata5.tkt.cn6 /export/python]$ ls20417.txt.utf-8 4300.txt.utf-8 5000-8.txt mapper.py reducer.py run.sh
上传文件到hadoop上面，命令如下：hadoop dfs -put ./*.txt /user/ticketdev/tmp （hadoop是配置好的，目录也是建立好的）
建立run.sh
hadoop jar $STREAM \-files ./mapper.py,./reducer.py \-mapper ./mapper.py \-reducer ./reducer.py \-input /user/ticketdev/tmp/*.txt \-output /user/ticketdev/tmp/output
查看结果：
[qiu.li@l-tdata5.tkt.cn6 /export/python]$ hadoop dfs -cat /user/ticketdev/tmp/output/part-00000 | sort -nk 2 |tail
DEPRECATED: Use ofthis script to execute hdfs command isdeprecated.
Instead use the hdfs commandforit.
it2387which2387that2668a3797
is 4097to5079
in 5226and7611of10388the20583
三、参考文献：
http://www.cnblogs.com/wing1995/p/hadoop.html?utm_source=tuicool&utm_medium=referral