public/subjects/devops/division/README.md

## 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

```console
$ ./divide.sh 4 1
4
$
```

### Hints

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

[Bash conditional construct](https://www.gnu.org/software/bash/manual/bash.html#Conditional-Constructs) can be used to decide whether to execute a specific command. Below an example `script.sh`.

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

And its output:

```console
$ bash script.sh
false
```

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

```bash
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:

```console
true
false
```

[bc](https://www.gnu.org/software/bc/manual/html_mono/bc.html) 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:

```console
$ echo "2 + 2" | bc
4
$
```