In this lesson, you will learn how to us arrays in Scala. Array in Scala works similar to arrays in Java, so let’s go ahead to get started!<\/p>\n
We’l cover the following sub-topics<\/p>\n
<\/p>\n
As you know, before you can use any variable, you must declare it. Arrays are not exceptions. You can declare an array variable in Scala using the syntax below:<\/p>\n
\/\/ Method 1<\/span>\r\nvar<\/span> arr:<\/span>Array<\/span>[<\/span>String<\/span>]<\/span> =<\/span> new<\/span> Array<\/span>[<\/span>String<\/span>](<\/span>3<\/span>)<\/span>\r\n\r\n\/\/ Method 2<\/span>\r\nvar<\/span> arr =<\/span> new<\/span> Array<\/span>[<\/span>String<\/span>](<\/span>3<\/span>)<\/span>\r\n<\/pre>\nIn these examples, we declare an array names arr, that can hold up to 3 String values.<\/p>\n
To access the elements of an array, you can use the index which is zero-based. Examples are given below:<\/p>\n
arr(<\/span>0<\/span>)<\/span> =<\/span> \"Kindson\"<\/span>;<\/span> \r\narr(<\/span>1<\/span>)<\/span> =<\/span> \"Jadon\"<\/span>;<\/span> \r\narr(<\/span>2<\/span>)<\/span> =<\/span> \"Solace\"<\/span>\r\n\r\n\/\/Another method<\/span>\r\nvar<\/span> arr =<\/span> Array<\/span>(<\/span>\"Kindson\"<\/span>,<\/span> \"Jadon\"<\/span>,<\/span> \"Solace\"<\/span>)<\/span>\r\n<\/pre>\nSo you can use either of the two methods<\/p>\n
<\/p>\n
2. Array Processing<\/strong><\/h4>\nNormally we can process multiple array elements using a loop. In the example below we perform the following operations:<\/p>\n
\n- Print all elements of the array<\/li>\n
- Sum all elements of the array<\/li>\n
- Find the maximum element in the array<\/li>\n<\/ul>\n
\/\/ Program to Demonstrate Array Processing<\/span>\r\nobject<\/span> ArrayProcessing<\/span> {<\/span>\r\n\r\n def<\/span> main(<\/span>args:<\/span> Array<\/span>[<\/span>String<\/span>])<\/span>:<\/span> Unit<\/span> =<\/span> {<\/span>\r\n\r\n val<\/span> arr =<\/span> Array<\/span>(<\/span>34<\/span>,<\/span> 66<\/span>,<\/span> 78<\/span>,<\/span> 3<\/span>,<\/span> 95<\/span>)<\/span>\r\n\r\n \/\/Print all element of the array<\/span>\r\n for<\/span> (<\/span>ele <-<\/span> arr)<\/span> {<\/span>\r\n println(<\/span>ele)<\/span>\r\n }<\/span>\r\n\r\n \/\/Sum all element of the array<\/span>\r\n var<\/span> sum:<\/span> Int<\/span> =<\/span> 0<\/span>\r\n for<\/span> (<\/span>ele <-<\/span> arr)<\/span> {<\/span>\r\n sum =<\/span> sum +<\/span> ele\r\n }<\/span>\r\n println(<\/span>s\"The sume is $sum\"<\/span>)<\/span>\r\n\r\n \/\/Find the maximum element<\/span>\r\n var<\/span> max =<\/span> arr(<\/span>0<\/span>)<\/span>\r\n for<\/span> (<\/span>i <-<\/span> 1<\/span> to (<\/span>arr.<\/span>length -<\/span> 1<\/span>))<\/span> {<\/span>\r\n if<\/span> (<\/span>arr(<\/span>i)<\/span> ><\/span> max)<\/span> {<\/span>\r\n max =<\/span> arr(<\/span>i)<\/span>\r\n }<\/span>\r\n }<\/span>\r\n println(<\/span>s\"The maximum number in the array is $max\"<\/span>)<\/span>\r\n }<\/span>\r\n}<\/span>\r\n<\/pre>\nThe program above gives the following output<\/p>\n
34\r\n66\r\n78\r\n3\r\n95\r\nThe sume is 276\r\nThe maximum number in the array is 95\r\n<\/pre>\n <\/p>\n
3. Multidimensional Arrays<\/strong><\/h4>\nYou can think of multidimensional array as an array of arrays. So we have the elements of the array to be arrays as well. That helps create a grid of table view of elements.<\/p>\n
The following syntax declares a 2-dimensional array called myGrid.<\/p>\n
var<\/span> myGrid =<\/span> ofDim[<\/span>Int<\/span>](<\/span>4<\/span>,<\/span>4<\/span>)<\/span>\r\n<\/pre>\nThe code above creates an array\u00a0 of 4 elements each being an array of 4 elements<\/p>\n
The program below creates a 2-dimensional array using a nested loop and then prints out the elements using another nested loop<\/p>\n
\/\/ Program to Demonstrate Multidimensional Array Processing<\/span>\r\nobject<\/span> MultidimensionalArray<\/span> {<\/span>\r\n\r\n def<\/span> main(<\/span>args:<\/span> Array<\/span>[<\/span>String<\/span>])<\/span>:<\/span> Unit<\/span> =<\/span> {<\/span>\r\n\r\n var<\/span> myGrid =<\/span> ofDim[<\/span>Int<\/span>](<\/span>4<\/span>,<\/span>4<\/span>)<\/span>\r\n\r\n \/\/Assign items to grid<\/span>\r\n for<\/span> (<\/span>i <-<\/span> 0<\/span> to (<\/span>myGrid.<\/span>length -<\/span>1<\/span>))<\/span> {<\/span>\r\n for<\/span> (<\/span>j <-<\/span> 0<\/span> to 3<\/span>)<\/span> {<\/span>\r\n myGrid(<\/span>i)(<\/span>j)<\/span> =<\/span> j\r\n }<\/span>\r\n }<\/span>\r\n\r\n \/\/Print out grid elements<\/span>\r\n for<\/span> (<\/span>i <-<\/span> 0<\/span> to (<\/span>myGrid.<\/span>length -<\/span>1<\/span>))<\/span> {<\/span>\r\n for<\/span> (<\/span>j <-<\/span> 0<\/span> to 3<\/span>)<\/span> {<\/span>\r\n print(<\/span>\" \"<\/span> +<\/span> myGrid(<\/span>i)(<\/span>j))<\/span>\r\n }<\/span>\r\n println()<\/span>\r\n }<\/span>\r\n\r\n }<\/span>\r\n}<\/span>\r\n<\/pre>\n