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我能够以 csv 格式获取列,如下所示:
,列1,列2,列3,列4,列5,,
我使用 awk 命令来获取以下格式的输出:
awk -vORS=, '$0 && p {print $2}; $2 == "name" {p=1} '`
然后我使用以下两个命令删除前导和尾随两个逗号:
cols=${cols:1}
cols=${cols:0:${#cols}-2}
现在我得到以下格式的输出:
列 1,列 2,列 3,列 4,列 5
我想从右侧删除与列表匹配的特定列。例如,如果我使用参数“col4,col5”调用该函数,awk 应该删除最后两列并打印输出,如下所示:
列1,列2,列3
如何在 shell 脚本中完成此操作(最好使用 awk 或 grep 或其他一些此类 shell 支持的命令)?
更新:初始文件内容以表格形式输出,如下所示:
+-----------------------------------------+--------+---------+
| name | type | comment |
+-----------------------------------------+--------+---------+
| col1 | int | |
| col2 | int | |
| col3 | string | |
| col4 | string | |
| col5 | string | |
+-----------------------------------------+--------+---------+
答案1
您可以使用“剪切”从分隔数据中提取某些列。例如,下面提取最后两列:
echo col1,col2,col3,col4,col5 | cut -d , -f 4,5
印刷
col4,col5
-d 参数指定分隔符,-f 指定您希望在结果中出现的结果字段的索引或索引范围
编辑
为了使其更加动态,下面将根据 Y 分隔符选择最后 X 列:
function lastCols {
endcol=$(($(head -n 1 $1 | grep -o , | wc -l) + 1))
startcol=$(($endcol-$2+1))
cut -d $3 -f $startcol-$endcol < $1
}
lastCols $1 $2 $3
我对此没有做过太多测试,所以可能有点问题。使用如下:
[]$ cat temp.txt
col1,col2,col3,col4,col5
col1,col2,col3,col4,col5
col1,col2,col3,col4,col5
col1,col2,col3,col4,col5
col1,col2,col3,col4,col5
col1,col2,col3,col4,col5
col1,col2,col3,col4,col5
col1,col2,col3,col4,col5
col1,col2,col3,col4,col5
[]$ ./lastCols.sh temp.txt 2 ,
col4,col5
col4,col5
col4,col5
col4,col5
col4,col5
col4,col5
col4,col5
col4,col5
col4,col5
答案2
这是我几年前为了解决这个问题而写的,当时我经常从事 OpenStack 工作,并对 OpenStack 工具的难以解析的输出感到恼火:
#! /usr/bin/perl
# untable.pl
#
# Copyright (C) 2012, 2013 Craig Sanders <[email protected]>
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2, or (at your option)
# any later version.
# script to strip mysql-style table formatting from nova, keystone,
# glance, etc commands
#
# also works for any tables output from mysql, and from tables produced
# by 'links -dump'
#
# makes the output easily parsable and usable in other scripts.
#
# TODO: command-line option to allow forcing of output style (2-column
# or multi-column) rather than detection.
use strict;
use Carp;
use Getopt::Long;
my $print_headers=0;
my $separator = '';
my $tab = '';
my $result = GetOptions("headers!" => \$print_headers,
"separator=s" => \$separator,
"tab" => \$tab,
);
$separator = "\t" if ($tab);
my $propval = -1;
our @headers;
while(<>) {
chomp;
next if (m/^\+/);
s/^\|\s*|\s*\|$//iog; # this / is here to fix SE''s broken perl syntax highlighting.
my @columns = split '\|';
# strip leading and trailing spaces
for my $col (0..scalar @columns-1) {
if ($columns[$col] eq '') {;
delete $columns[$col];
} else {
$columns[$col] =~ s/^\s+|\s+$//iog;
};
}
# find type of table - 2-column Property/Value, or multi-column
if ($propval == -1) {
if ($columns[0] eq 'Property') {
$propval = 1 ;
$separator = ": " if ($separator eq ''); # default to ': ' unless specified on cmd line
} else {
$propval = 0;
$separator = "\t" if ($separator eq ''); # default to TAB unless specified on cmd line
@headers = @columns;
print (join($separator,@headers),"\n") if $print_headers ;
};
next;
} else {
print join($separator,@columns),"\n" if (defined $columns[1]); # skip line unless we have more than one column to output
}
}
例子:
两列:
$ keystone tenant-get 93c14424ed06494c832457d974b9505e
+-------------+-----------------------------------------+
| Property | Value |
+-------------+-----------------------------------------+
| description | Anonymous Tenant Description |
| enabled | True |
| id | 93c14424ed06494c832457d974b9505e |
| name | ANON1 |
+-------------+-----------------------------------------+
$ keystone tenant-get 93c14424ed06494c832457d974b9505e | ./untable.pl
description: Anonymous Tenant Description
enabled: True
id: 93c14424ed06494c832457d974b9505e
name: ANON1
多栏:
$ keystone user-list 810
+-----+---------+-----------------------------+-----------------------------+
| id | enabled | email | name |
+-----+---------+-----------------------------+-----------------------------+
| 414 | 1 | [email protected] | [email protected] |
| 500 | 1 | [email protected] | [email protected] |
| 610 | 1 | [email protected] | [email protected] |
| 729 | 1 | [email protected] | [email protected] |
+-----+---------+-----------------------------+-----------------------------+
$ keystone user-list 810 | ./untable.pl
414 1 [email protected] [email protected]
500 1 [email protected] [email protected]
610 1 [email protected] [email protected]
729 1 [email protected] [email protected]