Software Shinobi
7d9171c854
All checks were successful
learn org at code.softwareshinobi.com/linux.softwareshinobi.com/pipeline/head This commit looks good
98 lines
1.6 KiB
Markdown
98 lines
1.6 KiB
Markdown
# Arrays
|
|
|
|
Arrays are essential. They let a single variable hold multiple values. Initialize them by listing values, separated by spaces, inside parentheses:
|
|
|
|
```bash
|
|
# Example initialization:
|
|
my_array=("value 1" "value 2" "value 3" "value 4")
|
|
```
|
|
|
|
Access array elements using their numeric index. **Always use curly brackets.**
|
|
|
|
Let's create `arrays.sh` to demonstrate:
|
|
|
|
```bash
|
|
touch arrays.sh
|
|
```
|
|
|
|
Now, open `arrays.sh` and add:
|
|
|
|
```bash
|
|
#!/usr/bin/env bash
|
|
|
|
my_array=("value 1" "value 2" "value 3" "value 4")
|
|
|
|
echo "Second element (index 1): ${my_array[1]}"
|
|
echo "Last element (index -1): ${my_array[-1]}"
|
|
echo "All elements: ${my_array[@]}"
|
|
echo "Total elements: ${#my_array[@]}"
|
|
```
|
|
|
|
Save and exit. Make it executable:
|
|
|
|
```bash
|
|
chmod +x arrays.sh
|
|
```
|
|
|
|
Run your script:
|
|
|
|
```bash
|
|
./arrays.sh
|
|
```
|
|
|
|
Output:
|
|
|
|
```
|
|
value 2
|
|
value 4
|
|
value 1 value 2 value 3 value 4
|
|
4
|
|
```
|
|
|
|
### Slicing
|
|
|
|
Extract specific portions of an array or string using slicing notation.
|
|
|
|
Create `slicing.sh`:
|
|
|
|
```bash
|
|
touch slicing.sh
|
|
```
|
|
|
|
Open `slicing.sh` and add these examples:
|
|
|
|
```bash
|
|
#!/usr/bin/env bash
|
|
|
|
letters=("A" "B" "C" "D" "E")
|
|
|
|
echo "Original array: ${letters[@]}"
|
|
|
|
echo "Example 1 (start 0, length 2): ${letters:0:2}" # Prints AB
|
|
echo "Example 2 (start 0, all elements): ${letters::5}" # Prints ABCDE
|
|
echo "Example 3 (start 3, to end): ${letters:3}" # Prints DE
|
|
```
|
|
|
|
Save and exit. Make it executable:
|
|
|
|
```bash
|
|
chmod +x slicing.sh
|
|
```
|
|
|
|
Run `slicing.sh`:
|
|
|
|
```bash
|
|
./slicing.sh
|
|
```
|
|
|
|
Output:
|
|
|
|
```
|
|
A B C D E
|
|
AB
|
|
ABCDE
|
|
DE
|
|
```
|
|
|
|
Mastering arrays and slicing gives you precise control over your data structures.
|