我想用SED一些列添加到默认值以下csv文件。
我的文件是这样的:
40,2012-05-30,London,61,Sunny
41,2012-02-22,Moscow,11,Snow
54,2012-04-10,Tokyo,02,Sunny
我想输出是:
40,2012-05-30,NULL,London,NULL,NULL,61,Sunny,Tom
41,2012-02-22,NULL,Moscow,NULL,NULL,11,Sunny,Tom
54,2012-04-10,NULL,Tokyo,NULL,NULL,02,Sunny,Tom
什么是最好的awk或者sed命令来获取所需的输出?
$ awk '{print $1,F,$2,F,F,$3,$4,$5,"Tom"}' FS=, OFS=, F='NULL' file
40,NULL,2012-05-30,NULL,NULL,London,61,Sunny,Tom
41,NULL,2012-02-22,NULL,NULL,Moscow,11,Snow,Tom
54,NULL,2012-04-10,NULL,NULL,Tokyo,02,Sunny,Tom
这是一系列基于这里的例子sed
命令:
s/31,/31,NULL,/;
s/,01/NULL,NULL,01/;
s/.$/,Tom/
至于awk
,也许你可以先插入域,后来更新它们:
BEGIN { FS="," }
{ print $1","$2",NULL,"$3",NULL,NULL,"$4","$5",Tom" }
如果你只是添加字段,你表现出那么这样的事情是好的:
$ awk 'BEGIN{FS=OFS=","} {$3="NULL,"$3",NULL,NULL"; $0=$0",Tom"} 1' file
40,2012-05-30,NULL,London,NULL,NULL,61,Sunny,Tom
41,2012-02-22,NULL,Moscow,NULL,NULL,11,Snow,Tom
54,2012-04-10,NULL,Tokyo,NULL,NULL,02,Sunny,Tom
但如果你正在做更重要的是那么有可能是针对涉及换挡领域更好的解决方案,并通过循环的结果与填充“NULL”空字段。