78 lines
2.7 KiB
JavaScript
78 lines
2.7 KiB
JavaScript
|
import { factory } from '../../utils/factory.js';
|
||
|
|
var name = 'matrixFromFunction';
|
||
|
|
var dependencies = ['typed', 'matrix', 'isZero'];
|
||
|
|
export var createMatrixFromFunction = /* #__PURE__ */factory(name, dependencies, _ref => {
|
||
|
|
var {
|
||
|
|
typed,
|
||
|
|
matrix,
|
||
|
|
isZero
|
||
|
|
} = _ref;
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Create a matrix by evaluating a generating function at each index.
|
||
|
|
* The simplest overload returns a multi-dimensional array as long as `size` is an array.
|
||
|
|
* Passing `size` as a Matrix or specifying a `format` will result in returning a Matrix.
|
||
|
|
*
|
||
|
|
* Syntax:
|
||
|
|
*
|
||
|
|
* math.matrixFromFunction(size, fn)
|
||
|
|
* math.matrixFromFunction(size, fn, format)
|
||
|
|
* math.matrixFromFunction(size, fn, format, datatype)
|
||
|
|
* math.matrixFromFunction(size, format, fn)
|
||
|
|
* math.matrixFromFunction(size, format, datatype, fn)
|
||
|
|
*
|
||
|
|
* Examples:
|
||
|
|
*
|
||
|
|
* math.matrixFromFunction([3,3], i => i[0] - i[1]) // an antisymmetric matrix
|
||
|
|
* math.matrixFromFunction([100, 100], 'sparse', i => i[0] - i[1] === 1 ? 4 : 0) // a sparse subdiagonal matrix
|
||
|
|
* math.matrixFromFunction([5], i => math.random()) // a random vector
|
||
|
|
*
|
||
|
|
* See also:
|
||
|
|
*
|
||
|
|
* matrix, zeros
|
||
|
|
*
|
||
|
|
* @param {Array | Matrix} size The size of the matrix to be created
|
||
|
|
* @param {function} fn Callback function invoked for every entry in the matrix
|
||
|
|
* @param {string} [format] The Matrix storage format, either `'dense'` or `'sparse'`
|
||
|
|
* @param {string} [datatype] Type of the values
|
||
|
|
* @return {Array | Matrix} Returns the created matrix
|
||
|
|
*/
|
||
|
|
return typed(name, {
|
||
|
|
'Array | Matrix, function, string, string': function ArrayMatrixFunctionStringString(size, fn, format, datatype) {
|
||
|
|
return _create(size, fn, format, datatype);
|
||
|
|
},
|
||
|
|
'Array | Matrix, function, string': function ArrayMatrixFunctionString(size, fn, format) {
|
||
|
|
return _create(size, fn, format);
|
||
|
|
},
|
||
|
|
'Matrix, function': function MatrixFunction(size, fn) {
|
||
|
|
return _create(size, fn, 'dense');
|
||
|
|
},
|
||
|
|
'Array, function': function ArrayFunction(size, fn) {
|
||
|
|
return _create(size, fn, 'dense').toArray();
|
||
|
|
},
|
||
|
|
'Array | Matrix, string, function': function ArrayMatrixStringFunction(size, format, fn) {
|
||
|
|
return _create(size, fn, format);
|
||
|
|
},
|
||
|
|
'Array | Matrix, string, string, function': function ArrayMatrixStringStringFunction(size, format, datatype, fn) {
|
||
|
|
return _create(size, fn, format, datatype);
|
||
|
|
}
|
||
|
|
});
|
||
|
|
|
||
|
|
function _create(size, fn, format, datatype) {
|
||
|
|
var m;
|
||
|
|
|
||
|
|
if (datatype !== undefined) {
|
||
|
|
m = matrix(format, datatype);
|
||
|
|
} else {
|
||
|
|
m = matrix(format);
|
||
|
|
}
|
||
|
|
|
||
|
|
m.resize(size);
|
||
|
|
m.forEach(function (_, index) {
|
||
|
|
var val = fn(index);
|
||
|
|
if (isZero(val)) return;
|
||
|
|
m.set(index, val);
|
||
|
|
});
|
||
|
|
return m;
|
||
|
|
}
|
||
|
|
});
|