parallax map
Recently I saw a few guys writing their code with inefficient map. I can't bear that and must point it out: Never map in void context instead of a for loop. When will map? You should only use a map when you expect a list as the result returned from it. Otherwise please use the regular for loop, which is faster and clearer. # time perl -e 'open STDOUT,">/dev/null";map { print $_ } 1 .. 1000000' ...
by 兰花仙子 - Perl - 2010-08-13 09:12:43 阅读（7357） 回复（24）
How map and Reduce operations are actually carried out Introduction This document describes how mapReduce operations are carried out in Hadoop. If you are not familiar with the Google mapReduce programming model you should get acquainted with it first. map As the map operation is parallelized the input file set is first split to several pieces called FileSplits . If an individual file is so ...
rootnoverify (hd1,0) map (hd0) (hd1) map (hd1) (hd0) chainloader +1 map命令一定要记得写两条 本文来自ChinaUnix博客，如果查看原文请点：http://blog.chinaunix.net/u1/47765/showart_1271451.html
google map 本文来自ChinaUnix博客，如果查看原文请点：http://blog.chinaunix.net/u/27042/showart_730145.html
java.util 接口 map 所有已知子接口： Concurrentmap , Sortedmap 所有已知实现类： Abstractmap , Attributes , AuthProvider , ConcurrentHashmap , Enummap , Hashmap , Hashtable , IdentityHashmap , LinkedHashmap , PrinterStateReasons , Properties , Provider , RenderingHints , TabularDataSupport , Treemap , UIDefaults , WeakHashmap public interface map 将键映射到值的对象。一个映射不能包...
本文重点介绍Hashmap。首先介绍一下什么是map。在数组中我们是通过数组下标来对其内容索引的，而在map中我们通过对象来对对象进行索引，用来索引的对象叫做key，其对应的对象叫做value。在下文中会有例子具体说明。 再来看看Hashmap和Treemap有什么区别。Hashmap通过hashcode对其内容进行快速查找，而 Treemap中所有的元素都保持着某种固定的顺序，如果你需要得到一个有序的结果你就应该使用Treemap（Hashmap中元素的排列顺序是不...
import java.util.map; import java.util.Hashmap; import java.util.Iterator; public class Test{ public static void main(String[] args){ map hashmap=new Hashmap(); hashmap.put("key1",new String("value1")); hashmap.put("key2",new String("value2")); hashmap.put("key3",new String("value3")); hashmap.put("key4",new String("value4")); hashmap.put("key5",new String("value5")); //创建Ha...
template <
typename KEY,
typename VALUE,
typename IMPL
>
class map
{
public:
typedef mapEntry
About Network Weathermap is a perl tool that displays in a visual way the utilization of the network links of your network. The required data are acquired from graphs created by the MRTG package and are displayed as two ways colored arrows on a map representing the logical topology of the network. The resulted image is presented in a web page using extra DHTML and JavaScript code for web-over pop...
我现在想在map中存储指针数据。那么当map构造之后，如果没有向里面添加记录，那么map里面的所有指针数据是否会初始化为NULL，或者不确定？？？ 假如不确定，我用iterator遍历的话，岂不是可能会非法读写内存？:oops: :shock: for (map_ITER itr=mymap.begin(); itr!=m_mymap.end(); itr++) pointer =(*itr).int_id_; ................ 我现在往map中加了一条记录，而且map的size也为1，但上面的遍历却循环了N次！是不是en...
1、nginx主配置文件 #cat nginx.conf http { map $old $new { include /etc/nginx/map/re.map; } include /etc/nginx/conf.d/*.conf; } 2、map文件 #cat map/re.map wode y; nide y; sheide h; 3、rewrite实现部分 #cat conf.d/rewrite.conf server { server_name 18.com set $old ""; if ( $new = "y" ) { set $rewrite_var_0 1; } if ( $rewrite_var...
