Multi-Dimensional Arrays

Multi-Dimensional Arrays

Arrays inside arrays (array-ception or “Yo, Dawg, I heard you like arrays, so I put an array inside your array” array)

Think of these like tables or matrices with multiple columns.

They have two indices per element (like coordinates - row, column)

Creating Two-Dimensional Arrays

Two-Dimensional arrays can be created with sets of initial values listed within curly brackets { }, then list these sets within outer curly brackets { }

Double square brackets [ ][ ] are placed right after the data type for all the elements of an array to signify it as a two-dimensional array.

Examples:

Processing:

// First and Last name and of 5 people
String[][] people = { 
    { "Charles", "Stanton" }, 
    { "Eric", "Straub" }, 
    { "Ellie", "Aderyn" },
    { "Betty", "Dean" },
    { "Alex", "Heber" }
};

How to picture it:

people	0	1
0	"Charles"	"Stanton"
1	"Eric"	"Straub"
2	"Ellie"	"Aderyn"
3	"Betty"	"Dean"
4	"Alex"	"Heber"

Using Two-Dimensional Arrays

Now, the elements can be accessed by their indices using both row and column.

Examples:

Processing:

println(people[0][0] + " " + people[0][1]);
 
// Prints "Charles Stanton"

Updating Two-Dimensional Arrays

Each “cell” can be updated individually like any other variable.

Examples:

Processing:

people[0][0] = "Charlie";

println(people[0][0] + " " + people[0][1]);
 
// Prints "Charlie Stanton"