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Multi-Dimensional Array in Scala

Multi-dimensional array in Scala is used to store data in matrix form i.e. in the form of multiple row and column. In this Scala tutorial, we will learn about multi-dimensional arrays in Scala and methods to create them with working code.
Submitted by Shivang Yadav, on July 01, 2019

Multi-dimensional arrays

An Array that stores data in the form multidimensional matrix. Multidimensional arrays are generally used for making matrices and tables in programming.

In Scala programming, there are two methods used to define a multidimensional array, They are :

1. Array.ofDim: Scala has inbuilt ofDim() method that creates multi-dimensional array.
2. Array of Array: Array of Array is used to create ragged array in Scala programming language.

1) Array.ofDim Method

Scala programming language has defined an inbuilt method ofDim() to create a multidimensional array. Using this method you can make an array upto 5-D. But to create an array with this method the exact number of rows and columns at the time of creation. The array first needs to be created first with the number of rows and columns you need and then your array is filled with values of elements.

Syntax:

    var arrayName = Array.ofDim[data_type](row, column) 
    Or 
    var arrayName = ofDim[data_type](row, column)

Both syntaxes are valid in Scala to create a multidimensional array.

Example:

object myObject 
    { 
        def main(args: Array[String]) 
        { 
            val multiArr= Array.ofDim[Int](3,2)  
            
            multiArr(0)(0) = 2                 
            multiArr(0)(1) = 7
            multiArr(1)(0) = 12
            multiArr(1)(1) = 43
            multiArr(2)(0) = 436
            multiArr(2)(1) = 672
          
            for(i <- 0 to 2; j <- 0 to 1){
                println("Element "+ i  + j + " = " + multiArr(i)(j))
            }
        } 
} 

Output

Element 00 = 2
Element 01 = 7
Element 10 = 12
Element 11 = 43
Element 20 = 436
Element 21 = 672

Code explanation:

The above code is the show creation of an array using the ofDim() method. The code creates a two-dimensional array with 3 rows and 2 columns. We have passed 3,2 as an argument for this. Next, in the code, we have initialized the value of each element of the array. At last, we have used a for loop with 2 variables to print the values of the array. The print statement is like this Element ij = value.

2) Array of Array

An alternate method to create a multidimensional array. The array of array creates a rugged array. A rugged array is an array that has each contained array of different sizes. Hence, it is an elegant method to create an array of arrays. In this array, we cannot separate initialization and value feeding.

Syntax:

    var arrayName = Array(Array(elements), Array(elements))

Syntax explanation:

This type of initialization is done keeping in mind that the array can be rugged. So, this is why we have defined an array that has arrays as its elements. Each array can have its own size. But the datatype should be the same.

Example:

object myObject 
    { 
        def main(args: Array[String]) 
        { 
            val multiArr= Array(Array(2,5,6),Array(12, 54,232))
            
            for(i <- 0 to 1; j <- 0 to 2){
                println("Element "+ i  + j + " = " + multiArr(i)(j))
            }
        } 
} 

Output

Element 00 = 2
Element 01 = 5
Element 02 = 6
Element 10 = 12
Element 11 = 54
Element 12 = 232

Code explanation:

The above code initializes a multidimensional array using an array of array. We have made an array with 2 rows and 3 columns with the help of this method, also than the number of columns for row 1 and row 2 can be different.