首页 > 移动平台 > 详细

[hadoop入门]mapper与reducer

时间:2018-11-24 00:37:04      阅读:204      评论:0      收藏:0      [点我收藏+]

1、mapper

#!/usr/bin/env python
import sys
for line in sys.stdin:
    line = line.strip()
    words = line.split()
    for word in words:
        print "%s\t%s" % (word, 1)

2、reducer

#!/usr/bin/env python
from operator import itemgetter
import sys

current_word = None
current_count = 0
word = None

for line in sys.stdin:
    line = line.strip()
    word, count = line.split(\t, 1)
    try:
        count = int(count)
    except ValueError:  #count如果不是数字的话,直接忽略掉
        continue
    if current_word == word:
        current_count += count
    else:
        if current_word:
            print "%s\t%s" % (current_word, current_count)
        current_count = count
        current_word = word

if word == current_word:  #不要忘记最后的输出
    print "%s\t%s" % (current_word, current_count)

 

3、提供权限命令

chmod +x  文件名

 

[hadoop入门]mapper与reducer

原文:https://www.cnblogs.com/elpsycongroo/p/10010327.html

(0)
(0)
   
举报
评论 一句话评论(0
关于我们 - 联系我们 - 留言反馈 - 联系我们:wmxa8@hotmail.com
© 2014 bubuko.com 版权所有
打开技术之扣,分享程序人生!