public/subjects/devops/division

division

Instructions

In this exercise, you will make a script division.sh that will take two arguments from the command line, and divide the first one by the second one.

You will need to handle what to do when the inputs are wrong.

If the divisor is 0 you will need to output Error: division by zero is not allowed.

If the arguments are not numbers, the output should be Error: both arguments must be numeric.

In the case where the number of arguments are not enough, the output should be Error: two numbers should be provided.

Your script should handle very large numbers as well.

For this exercise the use of the test command is not allowed.

Usage

$ ./divide.sh 4 1
4
$

Hints

You can use the following to help you solve this exercise:

Bash conditional construct can be used to decide whether to execute a specific command. Below an example script.sh.

#!/usr/bin/env bash
if [[ 1 > 2 ]]; then
    echo "true"
else
    echo "false"
fi

And its output:

$ bash script.sh
false

It is possible to combine several conditions with the AND (&&) and OR (||) logical operators. Below and example script.sh.

if [[ 1 > 2 ]] || [[ 1 == 1 ]]; then
    echo "true"
else
    echo "false"
fi
if [[ 1 > 2 ]] && [[ 1 == 1 ]]; then
    echo "true"
else
    echo "false"
fi

And its output:

true
false

bc is a Unix utility that performs arbitrary precision arithmetic. It is particularly useful to handle numbers that are too large. One way of using it is as below:

$ echo "2 + 2" | bc
4
$