How to Get the Width and Height of a Multi-Dimensional Array

How do you get the width and height of a multi-dimensional array?

You use Array.GetLength with the index of the dimension you wish to retrieve.

How do you get the width and height of a multi-dimensional array if i use it into Jagged Arrays?

var length = _EnemyPosition[0].Length; //returns 5 (5·1)
var length = _EnemyPosition[1].Length; //returns 10 (5·2)

Is that what you want? Your requirement is far from clear:

i want to know how to get length of this array: _EnemyPosition[1][0].length

That is not an array, _EnemyPostion[1] is a two dimensional array [,]. Consider the following analogue scenario:

int[,] myTwoDimensionalArray = ...
var whatever = myTwoDimensionalArray[0]; //not valid, array dimensiones don't match.

So, we have three options when it comes to the length you want returned:

1. _EnemyPosition[1].Length which returns the total length of the two dimensional array 10.
2. _EnemyPosition[1].GetLength(0) which returns the length of the first dimension of the two dimensional array 5
3. _EnemyPosition[1].GetLength(1) which returns the length of the second dimension of the two dimensional array 2

And obviously the result of 2 times 3 is 1. So, which one do you want?

Size of multi dimensional array

b is a 2D character array of rows 3 and columns 4.

So, if you take sizeof(b) you will get 12.

b[0] (and b[i] in general) has a type of a 1D character array of size 4. So. if you take sizeof (b[0]) you will get 4.

b[0][0] (and b[i][j] in general) has a type of char. So if you take sizeof (b[0][0]) you will get 1.

sizeof does not depend on the array index. The type remains the same even for b[0] and b[100], even though it might be out of range of the memory of the array.

C: Size of two dimensional array

That's a problem of integer division!

int column = sizeof(result[0])/row;

should be

int column = 7 / 10;

and in integer division, 7/10==0.

What you want to do is divide the length of one row, eg. sizeof(result[0]) by the size of one element of that row, eg. sizeof(result[0][0]):

int column = sizeof(result[0])/sizeof(result[0][0]);

How do I find the size of a 2D array?

You want the GetLength() method of your array:

a.GetLength(0);

http://msdn.microsoft.com/en-us/library/system.array.getlength.aspx

Simplify code: height and width of an 2d-array

const valid1 = [ // valid elements  [3, 2],  [3, 2]]const invalid1 = [ // different sizes  [1, 2],  [1]]const valid2 = [ // only 1 element  [1, 2]]
function sizes(bss) {  // avoid empty array (optional)  if (!bss.length) {    return 'invalid'  }  // is array same length with other elements  const isEqualLength = bss.every(function(v) {    return v.length === bss[bss.length - 1].length  })  if (isEqualLength) {    // get minimal values from each array element    const minBss = bss.map(function(v) {      return Math.min.apply(null, v)    })
    return {      width: minBss[0],      height: bss.length    }  }  return 'invalid'}
// check validconsole.log(sizes(valid1))// check invalid length of elements of arrayconsole.log(sizes(invalid1))// check invalid length of arrayconsole.log(sizes(valid2))

Finding Maximum Height and Width for 2D Array of Unknown Dimensions (Java)

Will .length still work?

A 2D array is just simply an array, where the items in it are other arrays. Since .length works on a 1D array, it will surely work on all arrays - the amount of dimensions does not matter.

However, pixels.length gives you the length of the parent array - i.e. the array that contains all of the other arrays inside it. To get the length of the second dimension, you will have to get the length of the arrays inside it.

So, how do we get the length of the 2nd dimension?

We know that all of these arrays must be the same length, so we use the one at position 0 only because it is the only one that we can be 100% sure will always exist - an array should always have at least one element.

Then, we just get the length of that array - pixels[0].length.

Getting the array length of a 2D array in Java

Consider

public static void main(String[] args) {

    int[][] foo = new int[][] {
        new int[] { 1, 2, 3 },
        new int[] { 1, 2, 3, 4},
    };

    System.out.println(foo.length); //2
    System.out.println(foo[0].length); //3
    System.out.println(foo[1].length); //4
}

Column lengths differ per row. If you're backing some data by a fixed size 2D array, then provide getters to the fixed values in a wrapper class.

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