Difference between revisions of "Command Line Examples: gawk"
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| Line 3: | Line 3: | ||
In the examples that follow, assume that a file name <code>test-data.txt</code> exists and contains 3 columns of data. | In the examples that follow, assume that a file name <code>test-data.txt</code> exists and contains 3 columns of data. | ||
| − | + | user@host: $ cat test-data.txt | |
1 11 21 | 1 11 21 | ||
2 12 22 | 2 12 22 | ||
3 13 23 | 3 13 23 | ||
4 14 24 | 4 14 24 | ||
| + | |||
| + | Print only columns 1 and 2 of the datafile | ||
| + | user@host: $ cat test-data.txt| gawk '{print $1,$2}' | ||
| + | 1 11 | ||
| + | 2 12 | ||
| + | 3 13 | ||
| + | 4 14 | ||
Revision as of 12:26, 20 February 2013
gawk is a powerful stream editor that can be used in command pipelines to perform special functions that do not have a command written for. The easiest use of gawk (and a very common one) is to manipulate the columns in text stream.
In the examples that follow, assume that a file name test-data.txt exists and contains 3 columns of data.
user@host: $ cat test-data.txt 1 11 21 2 12 22 3 13 23 4 14 24
Print only columns 1 and 2 of the datafile
user@host: $ cat test-data.txt| gawk '{print $1,$2}'
1 11
2 12
3 13
4 14
