Function subset

Get or set a subset of a matrix or string.

Syntax

subset(value, index)                                // retrieve a subset
subset(value, index, replacement [, defaultValue])  // replace a subset

Parameters

Parameter Type Description
matrix Array | Matrix | string An array, matrix, or string
index Index An index containing ranges for each dimension
replacement * An array, matrix, or scalar. If provided, the subset is replaced with replacement. If not provided, the subset is returned
defaultValue * Default value, filled in on new entries when the matrix is resized. If not provided, matrix elements will be left undefined. Default value: undefined.

Returns

Type Description
Array | Matrix | string Either the retrieved subset or the updated matrix.

Examples

// get a subset
var d = [[1, 2], [3, 4]];
subset(d, index(1, 0));        // returns 3
subset(d, index([0, 2], 1));   // returns [[2], [4]]

// replace a subset
var e = [];
var f = subset(e, index(0, [0, 2]), [5, 6]);  // f = [[5, 6]]
var g = subset(f, index(1, 1), 7, 0);         // g = [[5, 6], [0, 7]]

See also

size, resize, squeeze