as3 multidimensional array - actionscript-3

Question

Im trying to make a multidimensional array but I obtain an error ("TypeError: Error #1010: A term is undefined and has no properties.").
var matriz:Array = new Array();
for(var p:Number = 0; p<2;p++ ){
for(var q:Number = 0; q<2;q++ ){
matriz[p][q] = 0;
}
}
what am I doing wrong?
Thanks in advance!

Answer 1

You need to create an array within matriz[p] before you can add an array (or anything else) into it.
You can achieve what you're attempting without errors like this:
var matriz:Array = [];
for(var p:Number = 0; p<2; p++)
{
// Create an array at matriz[p] if undefined.
if(matriz[p] == undefined) matriz[p] = [];
for(var q:Number = 0; q<2; q++)
{
matriz[p][q] = 0;
}
}
Essentially you were trying to do the same as this:
var object:Object = {};
object.nonexistantProperty.value = 10;

Answer 2

What Marty has said is correct, however I prefer removing the if condition and changing the code to the following:
var matriz:Array = [];
for(var p:Number = 0; p<2; p++) {
matriz[p] = [];
for(var q:Number = 0; q<2; q++) {
matriz[p][q] = 0;
}
}

Answer 3

public class cArray
{
private var DIM1CAP:uint=0;
private var DIM2CAP:uint=1;
private var DIM3CAP:uint=2;
private var DIM4CAP:uint=3;
private var DIM5CAP:uint=4;
public function cArray():void
{
// avoid the noid
}
// returns empty array of args.length dimensions
// 1st argument is dim 1 capacity; 2nd is dim 2, etc.
public function getArray ( ... args ):Array
{
var arr = new Array();
if ( paramsNotValid(args) )
{
return null;
}
switch (args.length)
{
case 2:
arr = get2DArray ( args[0], args[1] );
break;
case 3:
arr = get3DArray ( args[0], args[1], args[2] );
break;
case 4:
arr = get4DArray ( args[0], args[1], args[2], args[3] );
break;
case 5:
arr = get5DArray ( args[0], args[1], args[2], args[3], args[4] );
break;
default:
break;
}
return arr;
}
// returns empty 2d array of parameter specified capacity
private function get2DArray ( _1stDimCapacity:uint, _2ndDimCapacity:uint ):Array
{
var arr2d:Array = [];
var arr1d = new Array();
for ( var i:uint=0; i<_1stDimCapacity; i++ )
{
arr1d[_2ndDimCapacity-1] = undefined;
arr2d.push(arr1d);
arr1d = new Array();
}
return arr2d;
}
// returns empty 3d array of parameter specified capacity
private function get3DArray ( dim1Cap:uint,
dim2Cap:uint,
dim3Cap:uint ):Array
{
var arr3d = new Array();
for ( var i:uint=0; i<dim1Cap; i++ )
{
arr3d.push ( get2DArray ( dim2Cap, dim3Cap ) );
}
return arr3d;
}
// returns empty 4d array of parameter specified capacity
private function get4DArray ( dim1Cap:uint,
dim2Cap:uint,
dim3Cap:uint,
dim4Cap:uint):Array
{
var arr4d = new Array();
for ( var i:uint=0; i<dim1Cap; i++ )
{
arr4d.push ( get3DArray ( dim2Cap, dim3Cap, dim4Cap ) );
}
return arr4d;
}
// returns empty 5d array of parameter specified capacity
private function get5DArray ( dim1Cap:uint,
dim2Cap:uint,
dim3Cap:uint,
dim4Cap:uint,
dim5Cap:uint):Array
{
var arr5d = new Array();
for ( var i:uint=0; i<dim1Cap; i++ )
{
arr5d.push ( get4DArray ( dim2Cap, dim3Cap, dim4Cap, dim5Cap ) );
}
return arr5d;
}
//////////////////////////////////////////////////////
private function paramsNotValid ( args:Array ):Boolean
{
if ( args.length<2 || args.length>5 )
{
return true;
}
for ( var i:uint=0; i<args.length; i++ )
{
if ( ! ( args[i]>0 ) )
{
break;
}
}
if ( i < args.length )
{
return true;
}
return false;
}
}
}
public class cMain extends MovieClip
{
var cArr:cArray = new cArray;
public function cMain():void
{
var arr2d:Array;
var arr3d:Array;
var chessBrd_4d:Array;
var arr5d:Array;
// capacity of 10 games; 150 moves/gm; white's mv or black's;
// - piece positions; move in chess notation (index 32 of
// - last dimension); commentary (index 33 of last dimension)
chessBrd_4d = cArr.getArray(10,150,2,34);
// adding data
// - 4th game, 8th move, white's move, positions of pieces
chessBrd_4d[3][7][0][0] = 'd8';
chessBrd_4d[3][7][0][1] = 'b1';
// ...
// - positions of pieces up to last one
// ...
// - last piece pos
chessBrd_4d[3][7][0][31] = 'captured';
// - actual move in chess notation
chessBrd_4d[3][7][0][32] = 'nC4';
// - annotation
chessBrd_4d[3][7][0][33] = 'blocks b pawn, ' +
'opens diag for c1 bishop, ' +
'Justin Beiber is a putz, ' +
'the president is liar'
trace ( 'piece 0 is on square ' + chessBrd_4d[3][7][0][0]);
trace ( 'piece 1 is on square ' + chessBrd_4d[3][7][0][1]);
trace ( ' ... ' )
trace ( 'piece 31 has been ' + chessBrd_4d[3][7][0][31]);
trace ( 'move: ' + chessBrd_4d[3][7][0][32]);
trace ( chessBrd_4d[3][7][0][33]);
/*
trace results:
piece 0 is on square d8
piece 1 is on square b1
...
piece 31 has been captured
move: nC4
blocks b pawn, opens diag for c1 bishop,
Justin Beiber is a putz, the president is liar
*/
/*
trace ( chessBrd_4d.length ); = 10
trace ( chessBrd_4d [ 2 ].length ); = 150
trace ( chessBrd_4d [ 2 ] [ 4 ].length ); = 2
trace ( chessBrd_4d [ 2 ] [ 4 ] [ 1 ].length ); = 34
trace ( chessBrd_4d [ 2 ] [ 4 ] [ 0 ] .length); = 34
*/
}
}