Classes | Collections > Ordered

Array2D : Collection : Object

two-dimensional array
Source: Array2D.sc

Description

Represents a two-dimensional array of data. The number of rows and columns is fixed.

NOTE: It is possible to implement a similar behaviour using an "array-of-arrays" - see the examples towards the bottom of this page for comparison.

Class Methods

Array2D.new(rows: 1, cols: 1)

Create an array of the specified size.

a = Array2D.new(3,4);
a[2,2] = 1;
a.postln

Array2D.fromArray(rows, cols, array)

Build an Array2D from the supplied array.

a = Array2D.fromArray(3,4, [9,8,7,6,5,4,3,2,1,2,3,4]);
a[2,2] = 1;
a.postln

Inherited class methods

Instance Methods

.at(row, col)

Get a value from the array.

a.at(2,3);
a[2,3];

.put(row, col, val)

Put a value into the array.

a.put(2,3, 72);
a[2,3] = 72;

.colsDo(func)

Iterate over the columns. Each column will be passed to func in turn.

a.colsDo(_.postln);

.rowsDo(func)

Iterate over the rows. Each row will be passed to func in turn.

a.rowsDo(_.postln);

.colAt(ci)

Retrieve a single column.

a.colAt(2);

.rowAt(ri)

Retrieve a single row.

a.rowAt(2);

.asArray

Return a flat array containing the elements.

a.postln;
a.asArray.postln;

Returns:

Inherited instance methods

Undocumented instance methods

.array

.cols

.do(func)

.rows

.with(aarray)

Examples

// "a" is an array-of-arrays
a = { { 100.0.rand }.dup(100) }.dup(100);
// "b" is an equivalent Array2D, made using the "fromArray" class method
b = Array2D.fromArray(100,100, a.flat);

// Accessing
a[15][22]
b[15, 22]

// Speed comparison 1: random access
bench { 100.do(a[100.rand][100.rand]) }
bench { 100.do(b[100.rand, 100.rand]) }

// Speed comparison 2: iteration
bench { 100.do(a.do { |row| row.do { |item| item * 2 } }) }
bench { 100.do(b.do { |item| item * 2 }) }