摘要:As we saw in the previous posts, Hadoop makes an heavy use of network transmissions for executing its jobs. As Doug Cutting (the creator of Hadoop) ex 阅读全文
实现Hadoop的Writable接口Implementing Writable interface of Hadoop
2016-03-15 21:23 by GarfieldEr007, 453 阅读, 0 推荐, 收藏, 编辑更为详细的介绍Hadoop combiners-More about Hadoop combiners
2016-03-15 21:21 by GarfieldEr007, 293 阅读, 0 推荐, 收藏, 编辑
摘要:Hadoop combiners are a very powerful tool to speed up our computations. We already saw what a combiner is in a previous post and we also have seen ano 阅读全文
计算均值mean的MapReduce程序Computing mean with MapReduce
2016-03-15 21:20 by GarfieldEr007, 265 阅读, 0 推荐, 收藏, 编辑
摘要:In this post we'll see how to compute the mean of the max temperatures of every month for the city of Milan. The temperature data is taken from http:/ 阅读全文
Hadoop Combiners
2016-03-15 21:19 by GarfieldEr007, 157 阅读, 0 推荐, 收藏, 编辑
摘要:In the last post and in the preceding one we saw how to write a MapReduce program for finding the top-n items of a data set. The difference between th 阅读全文
Top N之MapReduce程序加强版Enhanced MapReduce for Top N items
2016-03-15 21:18 by GarfieldEr007, 368 阅读, 0 推荐, 收藏, 编辑
摘要:In the last post we saw how to write a MapReduce program for finding the top-n items of a dataset. The code in the mapper emits a pair key-value for e 阅读全文
Top N的MapReduce程序MapReduce for Top N items
2016-03-15 21:16 by GarfieldEr007, 550 阅读, 0 推荐, 收藏, 编辑
摘要:In this post we'll see how to count the top-n items of a dataset; we'll again use the flatland book we used in a previous post: in that example we use 阅读全文
MapReduce模式MapReduce patterns
2016-03-15 21:15 by GarfieldEr007, 281 阅读, 0 推荐, 收藏, 编辑
摘要:After having modified and run a job in the last post, we can now examine which are the most frequent patterns we encounter in MapReduce programming. A 阅读全文
为Hadoop创建JAR包文件Creating a JAR for Hadoop
2016-03-15 21:14 by GarfieldEr007, 516 阅读, 0 推荐, 收藏, 编辑
摘要:We've seen the internals of MapReduce in the last post. Now we can make a little change to the WordCount and create a JAR for being executed by Hadoop 阅读全文
MapReduce任务分析与讨论MapReduce job explained
2016-03-15 21:11 by GarfieldEr007, 271 阅读, 0 推荐, 收藏, 编辑
摘要:In the last post we saw how to run a MapReduce job on Hadoop. Now we're going to analyze how a MapReduce program works. And, if you don't know what Ma 阅读全文
STL容器用法速查表:list,vector,stack,queue,deque,priority_queue,set,map
2016-03-15 19:27 by GarfieldEr007, 491 阅读, 0 推荐, 收藏, 编辑
摘要:set [unordered_set] map [unordered_map] multimap [unordered_multimap] insert emplace insert emplace(key,val) emplace(key,val) erase(key)=>erasednum er 阅读全文