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Commands tagged Text Processing

Terminal - Commands tagged Text Processing - 36 results

perl -ne '$. == 4 && print && exit'

2011-09-05 21:52:16

User: bashrc

Functions: perl

Tags: Text Processing sed

-1

Up
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Print just line 4 from a textfile

Perl version - just for completeness sake ;)

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sed '4!d'

2011-09-05 17:54:57

User: totti

Functions: sed

Tags: Text Processing sed

-1

Up
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Print just line 4 from a textfile

d --> delete

!d ---> delete others

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echo "abcde" | sed 's/./& /g'

2011-08-26 16:54:26

User: totti

Functions: echo sed

Tags: Text Processing sed

Up
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Matched string reference in replacement text

Use matched data and some other as replacement data

sort -R

2011-07-15 15:35:27

User: RyanM

Functions: sort

Tags: Text Processing Os X cat sort perl sorting text

Up
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Randomize lines (opposite of | sort)

Randomizes a file. The opposite of sort is sort -R!

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awk 'BEGIN{RS="\0"}{gsub(/\n/,"<SOMETEXT>");print}' file.txt

2010-12-12 21:43:22

User: __

Functions: awk

Tags: Text Processing awk newline line

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Join lines

awk version of 7210. Slightly longer, but expanding it to catch blank lines is easier:

awk 'BEGIN{RS="\0"}{gsub(/\n+/,"<SOMETEXT>");print}' file.txt

tr "\n" " " < file

2010-12-08 16:13:54

User: randy909

Functions: tr

Tags: Text Processing

Up
Down

Join lines

Even shorter. Stolen from comment posted by eightmillion.

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cat file | tr -d "\n"

2010-12-02 09:22:02

User: uzsolt

Functions: cat file tr

Tags: Text Processing

-1

Up
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Join lines

This command deletes the "newline" chars, so its output maybe unusable :)

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cat file | tr "\n" " "

2010-12-02 09:21:02

User: uzsolt

Functions: cat file tr

Tags: Text Processing

Up
Down

Join lines

It's works only when you replace '\n' to ONE character.

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perl -pe 'eof()||s/\n/<SOMETEXT>/g' file.txt

2010-12-02 01:19:27

User: eightmillion

Functions: perl

Tags: Text Processing perl

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Join lines

This command turns a multi-line file into a single line joined with <SOMETEXT>. To skip blank lines, use:

perl -pe '(eof()||s/^\s*$//)||s/\n/<SOMETEXT>/g' file.txt

find . -name "*noticia*" -name "*jhtm*" -name "*.tpl" -exec grep -li "id=\"col-direita\"" '{}' \; | xargs -n1 mate

2010-09-18 02:55:40

User: irae

Functions: find grep xargs

Tags: Text Processing find xargs grep mac mate textmate search

-2

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find files containing specifc pattern on filename and specific patternts in its content, open all in textmate

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figlet gunslinger_

2010-07-11 16:23:19

User: gunslinger_

Tags: Text Processing ascii

-5

Up
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Text to ascii art

convert your text to ascii art

sort -t $'\t' -k 2 input.txt

2010-07-11 12:58:51

User: postrational

Functions: sort

Tags: Text Processing sort cut bash tricks join

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Pass TAB as field separator to sort, join, cut, etc.

Use this BASH trick to create a variable containing the TAB character and pass it as the argument to sort, join, cut and other commands which don't understand the \t notation.

sort -t $'\t' ... join -t $'\t' ... cut -d $'\t' ...

cut -f 1 three-column.txt > first-column.txt

2010-07-11 10:13:45

User: postrational

Functions: cut

Tags: Text Processing bash extract oneliner while substitution

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Short one line while loop that outputs parameterized content from one file to another

There is a common command for outputting a field or list of fields from each line in a file. Why wouldn't you just use cut?

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sed -n '4{p;q}'

2010-07-10 00:26:22

User: kniht

Functions: sed

Tags: Text Processing sed

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Print just line 4 from a textfile

Prints the 4th line and then quits. (Credit goes to flatcap in comments: http://www.commandlinefu.com/commands/view/6031/print-just-line-4-from-a-textfile#comment.)

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tail -n +4 | head -n 1

2010-07-09 12:10:03

User: unixmonkey10745

Functions: head tail

Tags: Text Processing

-5

Up
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Print just line 4 from a textfile

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awk '{print $1}' < three-column.txt > first-column.txt

2010-07-09 04:00:05

User: infinull

Functions: awk

Tags: Text Processing bash extract oneliner while substitution

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Short one line while loop that outputs parameterized content from one file to another

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while read col1 col23; do echo $col1; done < three-column.txt > first-column.txt

2010-07-09 03:59:20

User: infinull

Functions: echo read

Tags: Text Processing bash extract oneliner while substitution

-5

Up
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Short one line while loop that outputs parameterized content from one file to another

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while read l; do echo ${l%% *}; done < three-column-list.txt > only-first-column.txt

2010-07-09 03:42:56

User: zed

Functions: echo read

Tags: Text Processing bash extract oneliner while substitution

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Short one line while loop that outputs parameterized content from one file to another

The above is an example of grabbing only the first column. You can define the start and end points specifically by chacater position using the following command:

while read l; do echo ${l:10:40}; done < three-column-list.txt > column-c10-c40.txt

Of course, it doesn't have to be a column, or extraction, it can be replacement

while read l; do echo ${l/foo/bar}; done < list-with-foo.txt > list-with-bar.txt

Read more about parameter expansion here:

http://wiki.bash-hackers.org/syntax/pe

Think of this as an alternative to awk or sed for file operations

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sed -n '4p'

2010-07-08 22:07:40

User: infinull

Functions: sed

Tags: Text Processing

Up
Down

Print just line 4 from a textfile

this method should be the fastest

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head -n X | tail -n 1

2010-07-08 22:06:39

User: infinull

Functions: head tail

Tags: Text Processing

-1

Up
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Print just line 4 from a textfile

using tail first won't do it because tail counts from the bottom of the file. You could do it this way but I don't suggest it

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awk 'NR==4'

2010-07-08 21:04:04

User: Aparicio

Functions: awk

Tags: Text Processing

Up
Down

Print just line 4 from a textfile

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tail -n 4 | head -n 1

2010-07-08 19:50:06

User: puddy

Functions: head tail

Tags: Text Processing

-7

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Print just line 4 from a textfile

tail -n X | head -n 1

prints a specific line, where X is the line number

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perl -wl -e '@f=<>; for $i (0 .. $#f) { $r=int rand ($i+1); @f[$i, $r]=@f[$r,$i] if ($i!=$r); } chomp @f; print join $/, @f;' try.txt

2009-12-21 21:15:55

User: JohnGH

Functions: join perl

Tags: Text Processing Os X cat sort perl sorting text

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Randomize lines (opposite of | sort)

print the lines of a file in randomized order

random -f <file>

2009-09-24 19:15:58

User: haplo

Tags: Text Processing Os X cat sort perl sorting text

Up
Down

Randomize lines (opposite of | sort)

random(6) - random lines from a file or random numbers

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cat ~/SortedFile.txt | perl -wnl -e '@f=<>; END{ foreach $i (reverse 0 .. $#f) { $r=int rand ($i+1); @f[$i, $r]=@f[$r,$i] unless ($i==$r); } chomp @f; foreach $line (@f){ print $line; }}'

2009-09-24 15:42:43

User: drewk

Functions: cat perl

Tags: Text Processing Os X cat sort perl sorting text

Up
Down

Randomize lines (opposite of | sort)

The sort utility is well used, but sometimes you want a little chaos. This will randomize the lines of a text file.

BTW, on OS X there is no

| sort -R

option! There is also no

| shuf

These are only in the newer GNU core...

This is also faster than the alternate of:

| awk 'BEGIN { srand() } { print rand() "\t" $0 }' | sort -n | cut -f2-

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