Go Multidimensional Array


Example

Multidimensional arrays are basically arrays containing others arrays as elements.
It is represented like [sizeDim1][sizeDim2]..[sizeLastDim]type, replacing sizeDim by numbers corresponding to the length of the dimention, and type by the type of data in the multidimensional array.

For example, [2][3]int is representing an array composed of 2 sub arrays of 3 int typed elements.
It can basically be the representation of a matrix of 2 lines and 3 columns.

So we can make huge dimensions number array like var values := [2017][12][31][24][60]int for example if you need to store a number for each minutes since Year 0.

To access this kind of array, for the last example, searching for the value of 2016-01-31 at 19:42, you will access values[2016][0][30][19][42] (because array indexes starts at 0 and not at 1 like days and months)

Some examples following:

// Defining a 2d Array to represent a matrix like
// 1 2 3     So with 2 lines and 3 columns;
// 4 5 6     
var multiDimArray := [2/*lines*/][3/*columns*/]int{ [3]int{1, 2, 3}, [3]int{4, 5, 6} }

// That can be simplified like this:
var simplified := [2][3]int{{1, 2, 3}, {4, 5, 6}}

// What does it looks like ?
fmt.Println(multiDimArray)
// > [[1 2 3] [4 5 6]]

fmt.Println(multiDimArray[0]) 
// > [1 2 3]    (first line of the array)

fmt.Println(multiDimArray[0][1])
// > 2          (cell of line 0 (the first one), column 1 (the 2nd one))
// We can also define array with as much dimensions as we need
// here, initialized with all zeros
var multiDimArray := [2][4][3][2]string{} 

fmt.Println(multiDimArray);
// Yeah, many dimensions stores many data
// > [[[["" ""] ["" ""]] [["" ""] ["" ""]] [["" ""] ["" ""]]]
//    [[["" ""] ["" ""]] [["" ""] ["" ""]] [["" ""] ["" ""]]]
//    [[["" ""] ["" ""]] [["" ""] ["" ""]] [["" ""] ["" ""]]]
//    [[["" ""] ["" ""]] [["" ""] ["" ""]] [["" ""] ["" ""]]]]
//   [[[["" ""] ["" ""]] [["" ""] ["" ""]] [["" ""] ["" ""]]]
//    [[["" ""] ["" ""]] [["" ""] ["" ""]] [["" ""] ["" ""]]]
//    [[["" ""] ["" ""]] [["" ""] ["" ""]] [["" ""] ["" ""]]]
//    [[["" ""] ["" ""]] [["" ""] ["" ""]] [["" ""] ["" ""]]]]
// We can set some values in the array's cells
multiDimArray[0][0][0][0] := "All zero indexes"  // Setting the first value
multiDimArray[1][3][2][1] := "All indexes to max"  // Setting the value at extreme location

fmt.Println(multiDimArray);
// If we could see in 4 dimensions, maybe we could see the result as a simple format
    
// > [[[["All zero indexes" ""] ["" ""]] [["" ""] ["" ""]] [["" ""] ["" ""]]]
//    [[["" ""] ["" ""]] [["" ""] ["" ""]] [["" ""] ["" ""]]]
//    [[["" ""] ["" ""]] [["" ""] ["" ""]] [["" ""] ["" ""]]]
//    [[["" ""] ["" ""]] [["" ""] ["" ""]] [["" ""] ["" ""]]]]
//   [[[["" ""] ["" ""]] [["" ""] ["" ""]] [["" ""] ["" ""]]]
//    [[["" ""] ["" ""]] [["" ""] ["" ""]] [["" ""] ["" ""]]]
//    [[["" ""] ["" ""]] [["" ""] ["" ""]] [["" ""] ["" ""]]]
//    [[["" ""] ["" ""]] [["" ""] ["" ""]] [["" ""] ["" "All indexes to max"]]]]