Popular lifehacks

How do you cut the last field in awk in Unix?

How do you cut the last field in awk in Unix?

The second part (either NF-=1 NF– or –NF ) is just subtracting one from the NF variable. This prevent the last field from being printed, because when you change a field (removing the last field in this case), awk re-construct $0 , concatenate all fields separated by space by default.

How do I print columns in awk?

How to do it…

  1. To print the fifth column, use the following command: $ awk ‘{ print $5 }’ filename.
  2. We can also print multiple columns and insert our custom string in between columns. For example, to print the permission and filename of each file in the current directory, use the following set of commands:

How do I print a specific line in awk?

Write a bash script to print a particular line from a file

  1. awk : $>awk ‘{if(NR==LINE_NUMBER) print $0}’ file.txt.
  2. sed : $>sed -n LINE_NUMBERp file.txt.
  3. head : $>head -n LINE_NUMBER file.txt | tail -n + LINE_NUMBER Here LINE_NUMBER is, which line number you want to print. Examples: Print a line from single file.

How do you print on awk?

To print a blank line, use print “” , where “” is the empty string. To print a fixed piece of text, use a string constant, such as “Don’t Panic” , as one item. If you forget to use the double-quote characters, your text is taken as an awk expression, and you will probably get an error.

How do you sum in awk?

How to Sum Values in Awk

  1. BEGIN{FS=”\t”; sum=0} The BEGIN block is only executed once at the beginning of the program.
  2. {sum+=$11} Here we increment the sum variable by the value in field 11 for each line.
  3. END{print sum} The END block is only executed once at the end of the program.

How do I show the 10th line of a file in Linux?

Below are three great ways to get the nth line of a file in Linux.

  1. head / tail. Simply using the combination of the head and tail commands is probably the easiest approach.
  2. sed. There are a couple of nice ways to do this with sed .
  3. awk. awk has a built in variable NR that keeps track of file/stream row numbers.

What does awk print do?

When the print statement is used to print numeric values, awk internally converts the number to a string of characters and prints that string. awk uses the sprintf function to do this conversion (see the Section 8.1.

How to print the last column of awk.txt?

As soon as you will hit the Enter key, all the values of the last column of the file awk.txt will appear on your terminal as shown in the following image. The awk command will read this column whereas the print command will be responsible for displaying its values on the terminal.

How to print the last column from a file?

In this article, we aim to walk you through the different methods of using the “awk” command to print the last column from a file. There are two different methods in which we can use the “awk” command to print the last column from a file.

Where does the AWK autosplit array start at?

The @F autosplit array starts at index [0] while awk fields start with $1. Did you tried to start from right to left by using the rev command? In this case you just need to print the 2nd column:

How to print the last two columns of ls-l?

If we want to print the last two columns of the ls -l command we can do it as follows: 1 ls -l | awk ‘ {i = 2; for (–i; i >= 0; i–) { printf “%st”,$ (NF-i)} print “”}’; If we want to print the last two columns of the /etc/passwd file we can do it as follows: