To find unique occurrences where the lines are not adjacent a file needs to be sorted before passing to uniq . uniq will operate as expected on the following file that is named authors. txt . As duplicates are adjacent uniq will return unique occurrences and send the result to standard output.
How do I get unique lines in a file?
Find unique lines
- The file must be sorted first. sort file | uniq -u will output to console for you. – …
- I think the reason sort file | uniq shows all the values 1 time is because it immediately prints the line it encounters the first time, and for the subsequent encounters, it just skips them. –
How do I get unique records in Unix?
Let us now see the different ways to find the duplicate record.
- Using sort and uniq: $ sort file | uniq -d Linux. …
- awk way of fetching duplicate lines: $ awk ‘{a[$0]++}END{for (i in a)if (a[i]>1)print i;}’ file Linux. …
- Using perl way: …
- Another perl way: …
- A shell script to fetch / find duplicate records:
What does uniq do in Linux?
The uniq command can count and print the number of repeated lines. Just like duplicate lines, we can filter unique lines (non-duplicate lines) as well and can also ignore case sensitivity. We can skip fields and characters before comparing duplicate lines and also consider characters for filtering lines.
What does uniq do in Unix?
uniq is a utility command on Unix, Plan 9, Inferno, and Unix-like operating systems which, when fed a text file or STDIN, outputs the text with adjacent identical lines collapsed to one, unique line of text.
What is the use of awk in Linux?
Awk is a utility that enables a programmer to write tiny but effective programs in the form of statements that define text patterns that are to be searched for in each line of a document and the action that is to be taken when a match is found within a line. Awk is mostly used for pattern scanning and processing.
How do I remove duplicate lines in Unix?
You need to use shell pipes along with the following two Linux command line utilities to sort and remove duplicate text lines:
- sort command – Sort lines of text files in Linux and Unix-like systems.
- uniq command – Rport or omit repeated lines on Linux or Unix.
How do you find repeated words in Linux?
Explanation
- First you can tokenize the words with grep -wo , each word is printed on a singular line.
- Then you can sort the tokenized words with sort .
- Finally can find consecutive unique or duplicate words with uniq . 3.1. uniq -c This prints the words and their count.
What is the use of CD in Linux?
Linux cd command is used to change the current working directory ( i.e., in which the current user is working). The “cd” stands for ‘change directory. ‘ It is one of the most frequently used commands in the Linux terminal.
Which command is used to identify files?
The ‘file’ command is used to identify the types of file. This command tests each argument and classifies it. The syntax is ‘file [option] File_name’.
What is PS EF command in Linux?
This command is used to find the PID (Process ID, Unique number of the process) of the process. Each process will have the unique number which is called as PID of the process.
Who WC Linux?
wc stands for word count. As the name implies, it is mainly used for counting purpose. It is used to find out number of lines, word count, byte and characters count in the files specified in the file arguments.
How does grep work in Linux?
Grep is a Linux / Unix command-line tool used to search for a string of characters in a specified file. The text search pattern is called a regular expression. When it finds a match, it prints the line with the result. The grep command is handy when searching through large log files.
How do I print unique lines in Linux?
uniq Command in LINUX with examples
- Syntax of uniq Command : …
- Options For uniq Command: …
- Using -c option : It tells the number of times a line was repeated. …
- Using -D option : It also prints only duplicate lines but not one per group. …
- Using -u option : It prints only the unique lines.
What is tr in shell script?
The tr command in UNIX is a command line utility for translating or deleting characters. It supports a range of transformations including uppercase to lowercase, squeezing repeating characters, deleting specific characters and basic find and replace. It can be used with UNIX pipes to support more complex translation.