jiangchengfeiyi-xiaochengxu/node_modules/mathjs/lib/cjs/function/matrix/matrixFromFunction.js
2025-01-02 11:13:50 +08:00

80 lines
2.8 KiB
JavaScript

"use strict";
Object.defineProperty(exports, "__esModule", {
value: true
});
exports.createMatrixFromFunction = void 0;
var _factory = require("../../utils/factory.js");
const name = 'matrixFromFunction';
const dependencies = ['typed', 'matrix', 'isZero'];
const createMatrixFromFunction = exports.createMatrixFromFunction = /* #__PURE__ */(0, _factory.factory)(name, dependencies, _ref => {
let {
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 (size, fn, format, datatype) {
return _create(size, fn, format, datatype);
},
'Array | Matrix, function, string': function (size, fn, format) {
return _create(size, fn, format);
},
'Matrix, function': function (size, fn) {
return _create(size, fn, 'dense');
},
'Array, function': function (size, fn) {
return _create(size, fn, 'dense').toArray();
},
'Array | Matrix, string, function': function (size, format, fn) {
return _create(size, fn, format);
},
'Array | Matrix, string, string, function': function (size, format, datatype, fn) {
return _create(size, fn, format, datatype);
}
});
function _create(size, fn, format, datatype) {
let m;
if (datatype !== undefined) {
m = matrix(format, datatype);
} else {
m = matrix(format);
}
m.resize(size);
m.forEach(function (_, index) {
const val = fn(index);
if (isZero(val)) return;
m.set(index, val);
});
return m;
}
});