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

94 lines
2.6 KiB
JavaScript

"use strict";
Object.defineProperty(exports, "__esModule", {
value: true
});
exports.createMatrixFromColumns = void 0;
var _factory = require("../../utils/factory.js");
const name = 'matrixFromColumns';
const dependencies = ['typed', 'matrix', 'flatten', 'size'];
const createMatrixFromColumns = exports.createMatrixFromColumns = /* #__PURE__ */(0, _factory.factory)(name, dependencies, _ref => {
let {
typed,
matrix,
flatten,
size
} = _ref;
/**
* Create a dense matrix from vectors as individual columns.
* If you pass row vectors, they will be transposed (but not conjugated!)
*
* Syntax:
*
* math.matrixFromColumns(...arr)
* math.matrixFromColumns(col1, col2)
* math.matrixFromColumns(col1, col2, col3)
*
* Examples:
*
* math.matrixFromColumns([1, 2, 3], [[4],[5],[6]])
* math.matrixFromColumns(...vectors)
*
* See also:
*
* matrix, matrixFromRows, matrixFromFunction, zeros
*
* @param {... Array | Matrix} cols Multiple columns
* @return { number[][] | Matrix } if at least one of the arguments is an array, an array will be returned
*/
return typed(name, {
'...Array': function (arr) {
return _createArray(arr);
},
'...Matrix': function (arr) {
return matrix(_createArray(arr.map(m => m.toArray())));
}
// TODO implement this properly for SparseMatrix
});
function _createArray(arr) {
if (arr.length === 0) throw new TypeError('At least one column is needed to construct a matrix.');
const N = checkVectorTypeAndReturnLength(arr[0]);
// create an array with empty rows
const result = [];
for (let i = 0; i < N; i++) {
result[i] = [];
}
// loop columns
for (const col of arr) {
const colLength = checkVectorTypeAndReturnLength(col);
if (colLength !== N) {
throw new TypeError('The vectors had different length: ' + (N | 0) + ' ≠ ' + (colLength | 0));
}
const f = flatten(col);
// push a value to each row
for (let i = 0; i < N; i++) {
result[i].push(f[i]);
}
}
return result;
}
function checkVectorTypeAndReturnLength(vec) {
const s = size(vec);
if (s.length === 1) {
// 1D vector
return s[0];
} else if (s.length === 2) {
// 2D vector
if (s[0] === 1) {
// row vector
return s[1];
} else if (s[1] === 1) {
// col vector
return s[0];
} else {
throw new TypeError('At least one of the arguments is not a vector.');
}
} else {
throw new TypeError('Only one- or two-dimensional vectors are supported.');
}
}
});