How to Iterate over a Range of Numbers in Bash

In the Bash command line interface, the for loop is often used to iterate over a range of numbers. This can be useful in a variety of situations, such as when you want to perform an operation on each item in a sequence or when you want to generate a sequence of numbers for some other purpose.

To iterate over a range of numbers in Bash, you can use the seq command, which generates a sequence of numbers. The basic syntax for the seq command is as follows:

seq [OPTION]... FIRST INCREMENT LAST

Here, FIRST is the first number in the sequence, INCREMENT is the amount by which each subsequent number in the sequence should be incremented, and LAST is the last number in the sequence.

So, for example, if you wanted to generate a sequence of numbers from 1 to 10 in increments of 1, you would use the following seq command:

seq 1 1 10

This would generate the following sequence of numbers:

1
2
3
4
5
6
7
8
9
10

Once you have generated a sequence of numbers using the seq command, you can use the for loop to iterate over the numbers in the sequence. The basic syntax for the for loop is as follows:

for VARIABLE in SEQUENCE
do
    COMMANDS
done

Here, VARIABLE is a placeholder for each item in the SEQUENCE, COMMANDS are the commands that should be executed for each item in the sequence, and SEQUENCE is the sequence of items over which the for loop should iterate.

We can use the seq and for commands and iterate over a range of numbers. To do so, you would use the seq command to generate the sequence of numbers, and then use the for loop to iterate over the numbers in the sequence:

for i in $(seq 1 1 10)
do
    COMMANDS
done

Here, the $(seq 1 1 10) part of the for loop generates the sequence of numbers from 1 to 10 in increments of 1, and the for loop iterates over the numbers in the sequence, with i being the current number in the sequence at each iteration.

Conclusion

The seq and for commands in Bash allow for easy iteration over a range of numbers. This is a great tool for automating tasks and working with sequences of numbers in the Bash command line interface. For example, to perform an operation a repeated number of times.