import _extends from "@babel/runtime/helpers/extends"; import { factory } from '../../utils/factory.js'; import { format } from '../../utils/string.js'; import { createComplexEigs } from './eigs/complexEigs.js'; import { createRealSymmetric } from './eigs/realSymmetric.js'; import { typeOf, isNumber, isBigNumber, isComplex, isFraction } from '../../utils/is.js'; var name = 'eigs'; // The absolute state of math.js's dependency system: var dependencies = ['config', 'typed', 'matrix', 'addScalar', 'equal', 'subtract', 'abs', 'atan', 'cos', 'sin', 'multiplyScalar', 'divideScalar', 'inv', 'bignumber', 'multiply', 'add', 'larger', 'column', 'flatten', 'number', 'complex', 'sqrt', 'diag', 'size', 'reshape', 'qr', 'usolve', 'usolveAll', 'im', 're', 'smaller', 'matrixFromColumns', 'dot']; export var createEigs = /* #__PURE__ */factory(name, dependencies, _ref => { var { config, typed, matrix, addScalar, subtract, equal, abs, atan, cos, sin, multiplyScalar, divideScalar, inv, bignumber, multiply, add, larger, column, flatten, number, complex, sqrt, diag, size, reshape, qr, usolve, usolveAll, im, re, smaller, matrixFromColumns, dot } = _ref; var doRealSymmetric = createRealSymmetric({ config, addScalar, subtract, column, flatten, equal, abs, atan, cos, sin, multiplyScalar, inv, bignumber, complex, multiply, add }); var doComplexEigs = createComplexEigs({ config, addScalar, subtract, multiply, multiplyScalar, flatten, divideScalar, sqrt, abs, bignumber, diag, size, reshape, qr, inv, usolve, usolveAll, equal, complex, larger, smaller, matrixFromColumns, dot }); /** * Compute eigenvalues and optionally eigenvectors of a square matrix. * The eigenvalues are sorted by their absolute value, ascending, and * returned as a vector in the `values` property of the returned project. * An eigenvalue with algebraic multiplicity k will be listed k times, so * that the returned `values` vector always has length equal to the size * of the input matrix. * * The `eigenvectors` property of the return value provides the eigenvectors. * It is an array of plain objects: the `value` property of each gives the * associated eigenvalue, and the `vector` property gives the eigenvector * itself. Note that the same `value` property will occur as many times in * the list provided by `eigenvectors` as the geometric multiplicity of * that value. * * If the algorithm fails to converge, it will throw an error – * in that case, however, you may still find useful information * in `err.values` and `err.vectors`. * * Note that the 'precision' option does not directly specify the _accuracy_ * of the returned eigenvalues. Rather, it determines how small an entry * of the iterative approximations to an upper triangular matrix must be * in order to be considered zero. The actual accuracy of the returned * eigenvalues may be greater or less than the precision, depending on the * conditioning of the matrix and how far apart or close the actual * eigenvalues are. Note that currently, relatively simple, "traditional" * methods of eigenvalue computation are being used; this is not a modern, * high-precision eigenvalue computation. That said, it should typically * produce fairly reasonable results. * * Syntax: * * math.eigs(x, [prec]) * math.eigs(x, {options}) * * Examples: * * const { eigs, multiply, column, transpose, matrixFromColumns } = math * const H = [[5, 2.3], [2.3, 1]] * const ans = eigs(H) // returns {values: [E1,E2...sorted], eigenvectors: [{value: E1, vector: v2}, {value: e, vector: v2}, ...] * const E = ans.values * const V = ans.eigenvectors * multiply(H, V[0].vector)) // returns multiply(E[0], V[0].vector)) * const U = matrixFromColumns(...V.map(obj => obj.vector)) * const UTxHxU = multiply(transpose(U), H, U) // diagonalizes H if possible * E[0] == UTxHxU[0][0] // returns true always * * // Compute only approximate eigenvalues: * const {values} = eigs(H, {eigenvectors: false, precision: 1e-6}) * * See also: * * inv * * @param {Array | Matrix} x Matrix to be diagonalized * * @param {number | BigNumber | OptsObject} [opts] Object with keys `precision`, defaulting to config.relTol, and `eigenvectors`, defaulting to true and specifying whether to compute eigenvectors. If just a number, specifies precision. * @return {{values: Array|Matrix, eigenvectors?: Array}} Object containing an array of eigenvalues and an array of {value: number|BigNumber, vector: Array|Matrix} objects. The eigenvectors property is undefined if eigenvectors were not requested. * */ return typed('eigs', { // The conversion to matrix in the first two implementations, // just to convert back to an array right away in // computeValuesAndVectors, is unfortunate, and should perhaps be // streamlined. It is done because the Matrix object carries some // type information about its entries, and so constructing the matrix // is a roundabout way of doing type detection. Array: function Array(x) { return doEigs(matrix(x)); }, 'Array, number|BigNumber': function Array_numberBigNumber(x, prec) { return doEigs(matrix(x), { precision: prec }); }, 'Array, Object'(x, opts) { return doEigs(matrix(x), opts); }, Matrix: function Matrix(mat) { return doEigs(mat, { matricize: true }); }, 'Matrix, number|BigNumber': function Matrix_numberBigNumber(mat, prec) { return doEigs(mat, { precision: prec, matricize: true }); }, 'Matrix, Object': function Matrix_Object(mat, opts) { var useOpts = { matricize: true }; _extends(useOpts, opts); return doEigs(mat, useOpts); } }); function doEigs(mat) { var _opts$precision; var opts = arguments.length > 1 && arguments[1] !== undefined ? arguments[1] : {}; var computeVectors = 'eigenvectors' in opts ? opts.eigenvectors : true; var prec = (_opts$precision = opts.precision) !== null && _opts$precision !== void 0 ? _opts$precision : config.relTol; var result = computeValuesAndVectors(mat, prec, computeVectors); if (opts.matricize) { result.values = matrix(result.values); if (computeVectors) { result.eigenvectors = result.eigenvectors.map(_ref2 => { var { value, vector } = _ref2; return { value, vector: matrix(vector) }; }); } } if (computeVectors) { Object.defineProperty(result, 'vectors', { enumerable: false, // to make sure that the eigenvectors can still be // converted to string. get: () => { throw new Error('eigs(M).vectors replaced with eigs(M).eigenvectors'); } }); } return result; } function computeValuesAndVectors(mat, prec, computeVectors) { var arr = mat.toArray(); // NOTE: arr is guaranteed to be unaliased // and so safe to modify in place var asize = mat.size(); if (asize.length !== 2 || asize[0] !== asize[1]) { throw new RangeError("Matrix must be square (size: ".concat(format(asize), ")")); } var N = asize[0]; if (isReal(arr, N, prec)) { coerceReal(arr, N); // modifies arr by side effect if (isSymmetric(arr, N, prec)) { var _type = coerceTypes(mat, arr, N); // modifies arr by side effect return doRealSymmetric(arr, N, prec, _type, computeVectors); } } var type = coerceTypes(mat, arr, N); // modifies arr by side effect return doComplexEigs(arr, N, prec, type, computeVectors); } /** @return {boolean} */ function isSymmetric(arr, N, prec) { for (var i = 0; i < N; i++) { for (var j = i; j < N; j++) { // TODO proper comparison of bignum and frac if (larger(bignumber(abs(subtract(arr[i][j], arr[j][i]))), prec)) { return false; } } } return true; } /** @return {boolean} */ function isReal(arr, N, prec) { for (var i = 0; i < N; i++) { for (var j = 0; j < N; j++) { // TODO proper comparison of bignum and frac if (larger(bignumber(abs(im(arr[i][j]))), prec)) { return false; } } } return true; } function coerceReal(arr, N) { for (var i = 0; i < N; i++) { for (var j = 0; j < N; j++) { arr[i][j] = re(arr[i][j]); } } } /** @return {'number' | 'BigNumber' | 'Complex'} */ function coerceTypes(mat, arr, N) { /** @type {string} */ var type = mat.datatype(); if (type === 'number' || type === 'BigNumber' || type === 'Complex') { return type; } var hasNumber = false; var hasBig = false; var hasComplex = false; for (var i = 0; i < N; i++) { for (var j = 0; j < N; j++) { var el = arr[i][j]; if (isNumber(el) || isFraction(el)) { hasNumber = true; } else if (isBigNumber(el)) { hasBig = true; } else if (isComplex(el)) { hasComplex = true; } else { throw TypeError('Unsupported type in Matrix: ' + typeOf(el)); } } } if (hasBig && hasComplex) { console.warn('Complex BigNumbers not supported, this operation will lose precission.'); } if (hasComplex) { for (var _i = 0; _i < N; _i++) { for (var _j = 0; _j < N; _j++) { arr[_i][_j] = complex(arr[_i][_j]); } } return 'Complex'; } if (hasBig) { for (var _i2 = 0; _i2 < N; _i2++) { for (var _j2 = 0; _j2 < N; _j2++) { arr[_i2][_j2] = bignumber(arr[_i2][_j2]); } } return 'BigNumber'; } if (hasNumber) { for (var _i3 = 0; _i3 < N; _i3++) { for (var _j3 = 0; _j3 < N; _j3++) { arr[_i3][_j3] = number(arr[_i3][_j3]); } } return 'number'; } else { throw TypeError('Matrix contains unsupported types only.'); } } });