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Advanced "cut" Command Usage

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The cut command is a powerful tool for manipulating text data by selecting specific columns or fields from a line of text. It's particularly useful when working with structured data that is separated by delimiters like spaces, tabs, or commas.

Let's dive into the basics of the cut command:



Common Options:

  • -f: Specify the fields/columns to cut.
  • -d: Set the delimiter character.
  • --complement: Select everything except the specified fields.
  • -s: Suppress lines without delimiters.


Example 1: Cutting by Delimiter

Suppose you have a file named data.txt containing the following data:

John,25,New York
Alice,30,Los Angeles

To extract only the first field (Name), you can use the -f option:

cut -d ',' -f 1 data.txt

This command specifies a comma as the delimiter and selects the first field. The output will be:


Example 2: Cutting Multiple Fields

To extract both the Name and Location fields, you can specify multiple field numbers separated by commas:

cut -d ',' -f 1,3 data.txt

This will give you:

John,New York
Alice,Los Angeles

Example 3: Cutting by Character Position

You can also use cut to extract specific character ranges. For example, to extract characters 2-5 from each line:

echo "Hello,World" | cut -c 2-5

This will output:


Example 4: Complementing Fields

To select everything except the first field, use the --complement option:

cut -d ',' --complement -f 1 data.txt

This will output:

25,New York
30,Los Angeles

Example 5: Suppressing Lines without Delimiters

If you want to suppress lines that don't contain the delimiter (in this case, lines without commas), you can use the -s option:

cut -d ',' -f 2 data.txt

This will only display lines where the delimiter is found in the second field:


These are some common use cases of the cut command in Linux. It's a versatile tool that can help you manipulate and extract specific data from text files easily. Feel free to explore more options and combinations to suit your needs.

Example 6: Specifying a Custom Delimiter

You can use the -d option to specify a custom delimiter other than the default tab character. For example, if your data is delimited by colons (:), you can use the following command:

cut -d ':' -f 1,3 data.txt

This command extracts the first and third fields using colons as delimiters.

Example 7: Ranges of Fields

Instead of specifying individual fields, you can specify a range of fields using a hyphen (-). For instance, to extract fields 2 to 4, you can do:

cut -d ',' -f 2-4 data.txt

This command will give you the second, third, and fourth fields from each line.

Example 8: Reordering Fields

You can use cut in combination with other commands like paste to reorder fields. For example, to switch the order of fields 2 and 3, you can do:

cut -d ',' -f 1,3,2 data.txt

This command will rearrange the fields as follows:

John,New York,25
Alice,Los Angeles,30

Example 9: Using a File as Input

While we've been using inline data so far, you can also use the cut command with files. For instance:

cut -d ',' -f 1,2 < data.txt

This command will extract the first and second fields from the data.txt file.

Example 10: Delimiting by Tab

If your data is tab-separated, you can use a literal tab character as the delimiter. You might need to enter the tab character as Ctrl+V followed by Tab. For example:

cut -d $'t' -f 1,3 data.txt

This command extracts the first and third fields from tab-delimited data.

Example 11: Removing Header Lines

To remove header lines (lines containing column names), you can use tail to skip the first line and then apply cut. For example:

tail -n +2 data.txt | cut -d ',' -f 2

This will skip the header line and then extract the second field from each subsequent line.

Example 12: Counting Fields

If you want to count the number of fields in each line, you can use cut in combination with awk:

cut -d ',' -f 1,2,3 data.txt | awk -F ',' '{print NF}'

This command extracts the specified fields and then uses awk to count and print the number of fields in each line.

These examples should give you a deeper understanding of the cut command and its flexibility in manipulating text data in Linux. You can combine cut with other Unix/Linux commands to perform more complex text processing tasks tailored to your specific needs.