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Math.js is an extensive math library for JavaScript and Node.js. It features a flexible expression parser with support for symbolic computation, comes with a large set of built-in functions and constants, and offers an integrated solution to work with dif

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import { isArray, isBigNumber, isCollection, isIndex, isMatrix, isNumber, isString, typeOf } from '../../utils/is.js'; import { isInteger } from '../../utils/number.js'; import { format } from '../../utils/string.js'; import { clone, deepStrictEqual } from '../../utils/object.js'; import { arraySize, getArrayDataType, processSizesWildcard, unsqueeze, validateIndex } from '../../utils/array.js'; import { factory } from '../../utils/factory.js'; import { DimensionError } from '../../error/DimensionError.js'; import { optimizeCallback } from '../../utils/optimizeCallback.js'; var name = 'SparseMatrix'; var dependencies = ['typed', 'equalScalar', 'Matrix']; export var createSparseMatrixClass = /* #__PURE__ */factory(name, dependencies, _ref => { var { typed, equalScalar, Matrix } = _ref; /** * Sparse Matrix implementation. This type implements * a [Compressed Column Storage](https://en.wikipedia.org/wiki/Sparse_matrix#Compressed_sparse_column_(CSC_or_CCS)) * format for two-dimensional sparse matrices. * @class SparseMatrix */ function SparseMatrix(data, datatype) { if (!(this instanceof SparseMatrix)) { throw new SyntaxError('Constructor must be called with the new operator'); } if (datatype && !isString(datatype)) { throw new Error('Invalid datatype: ' + datatype); } if (isMatrix(data)) { // create from matrix _createFromMatrix(this, data, datatype); } else if (data && isArray(data.index) && isArray(data.ptr) && isArray(data.size)) { // initialize fields this._values = data.values; this._index = data.index; this._ptr = data.ptr; this._size = data.size; this._datatype = datatype || data.datatype; } else if (isArray(data)) { // create from array _createFromArray(this, data, datatype); } else if (data) { // unsupported type throw new TypeError('Unsupported type of data (' + typeOf(data) + ')'); } else { // nothing provided this._values = []; this._index = []; this._ptr = [0]; this._size = [0, 0]; this._datatype = datatype; } } function _createFromMatrix(matrix, source, datatype) { // check matrix type if (source.type === 'SparseMatrix') { // clone arrays matrix._values = source._values ? clone(source._values) : undefined; matrix._index = clone(source._index); matrix._ptr = clone(source._ptr); matrix._size = clone(source._size); matrix._datatype = datatype || source._datatype; } else { // build from matrix data _createFromArray(matrix, source.valueOf(), datatype || source._datatype); } } function _createFromArray(matrix, data, datatype) { // initialize fields matrix._values = []; matrix._index = []; matrix._ptr = []; matrix._datatype = datatype; // discover rows & columns, do not use math.size() to avoid looping array twice var rows = data.length; var columns = 0; // equal signature to use var eq = equalScalar; // zero value var zero = 0; if (isString(datatype)) { // find signature that matches (datatype, datatype) eq = typed.find(equalScalar, [datatype, datatype]) || equalScalar; // convert 0 to the same datatype zero = typed.convert(0, datatype); } // check we have rows (empty array) if (rows > 0) { // column index var j = 0; do { // store pointer to values index matrix._ptr.push(matrix._index.length); // loop rows for (var i = 0; i < rows; i++) { // current row var row = data[i]; // check row is an array if (isArray(row)) { // update columns if needed (only on first column) if (j === 0 && columns < row.length) { columns = row.length; } // check row has column if (j < row.length) { // value var v = row[j]; // check value != 0 if (!eq(v, zero)) { // store value matrix._values.push(v); // index matrix._index.push(i); } } } else { // update columns if needed (only on first column) if (j === 0 && columns < 1) { columns = 1; } // check value != 0 (row is a scalar) if (!eq(row, zero)) { // store value matrix._values.push(row); // index matrix._index.push(i); } } } // increment index j++; } while (j < columns); } // store number of values in ptr matrix._ptr.push(matrix._index.length); // size matrix._size = [rows, columns]; } SparseMatrix.prototype = new Matrix(); /** * Create a new SparseMatrix */ SparseMatrix.prototype.createSparseMatrix = function (data, datatype) { return new SparseMatrix(data, datatype); }; /** * Attach type information */ Object.defineProperty(SparseMatrix, 'name', { value: 'SparseMatrix' }); SparseMatrix.prototype.constructor = SparseMatrix; SparseMatrix.prototype.type = 'SparseMatrix'; SparseMatrix.prototype.isSparseMatrix = true; /** * Get the matrix type * * Usage: * const matrixType = matrix.getDataType() // retrieves the matrix type * * @memberOf SparseMatrix * @return {string} type information; if multiple types are found from the Matrix, it will return "mixed" */ SparseMatrix.prototype.getDataType = function () { return getArrayDataType(this._values, typeOf); }; /** * Get the storage format used by the matrix. * * Usage: * const format = matrix.storage() // retrieve storage format * * @memberof SparseMatrix * @return {string} The storage format. */ SparseMatrix.prototype.storage = function () { return 'sparse'; }; /** * Get the datatype of the data stored in the matrix. * * Usage: * const format = matrix.datatype() // retrieve matrix datatype * * @memberof SparseMatrix * @return {string} The datatype. */ SparseMatrix.prototype.datatype = function () { return this._datatype; }; /** * Create a new SparseMatrix * @memberof SparseMatrix * @param {Array} data * @param {string} [datatype] */ SparseMatrix.prototype.create = function (data, datatype) { return new SparseMatrix(data, datatype); }; /** * Get the matrix density. * * Usage: * const density = matrix.density() // retrieve matrix density * * @memberof SparseMatrix * @return {number} The matrix density. */ SparseMatrix.prototype.density = function () { // rows & columns var rows = this._size[0]; var columns = this._size[1]; // calculate density return rows !== 0 && columns !== 0 ? this._index.length / (rows * columns) : 0; }; /** * Get a subset of the matrix, or replace a subset of the matrix. * * Usage: * const subset = matrix.subset(index) // retrieve subset * const value = matrix.subset(index, replacement) // replace subset * * @memberof SparseMatrix * @param {Index} index * @param {Array | Matrix | *} [replacement] * @param {*} [defaultValue=0] Default value, filled in on new entries when * the matrix is resized. If not provided, * new matrix elements will be filled with zeros. */ SparseMatrix.prototype.subset = function (index, replacement, defaultValue) { // check it is a pattern matrix if (!this._values) { throw new Error('Cannot invoke subset on a Pattern only matrix'); } // check arguments switch (arguments.length) { case 1: return _getsubset(this, index); // intentional fall through case 2: case 3: return _setsubset(this, index, replacement, defaultValue); default: throw new SyntaxError('Wrong number of arguments'); } }; function _getsubset(matrix, idx) { // check idx if (!isIndex(idx)) { throw new TypeError('Invalid index'); } var isScalar = idx.isScalar(); if (isScalar) { // return a scalar return matrix.get(idx.min()); } // validate dimensions var size = idx.size(); if (size.length !== matrix._size.length) { throw new DimensionError(size.length, matrix._size.length); } // vars var i, ii, k, kk; // validate if any of the ranges in the index is out of range var min = idx.min(); var max = idx.max(); for (i = 0, ii = matrix._size.length; i < ii; i++) { validateIndex(min[i], matrix._size[i]); validateIndex(max[i], matrix._size[i]); } // matrix arrays var mvalues = matrix._values; var mindex = matrix._index; var mptr = matrix._ptr; // rows & columns dimensions for result matrix var rows = idx.dimension(0); var columns = idx.dimension(1); // workspace & permutation vector var w = []; var pv = []; // loop rows in resulting matrix rows.forEach(function (i, r) { // update permutation vector pv[i] = r[0]; // mark i in workspace w[i] = true; }); // result matrix arrays var values = mvalues ? [] : undefined; var index = []; var ptr = []; // loop columns in result matrix columns.forEach(function (j) { // update ptr ptr.push(index.length); // loop values in column j for (k = mptr[j], kk = mptr[j + 1]; k < kk; k++) { // row i = mindex[k]; // check row is in result matrix if (w[i] === true) { // push index index.push(pv[i]); // check we need to process values if (values) { values.push(mvalues[k]); } } } }); // update ptr ptr.push(index.length); // return matrix return new SparseMatrix({ values, index, ptr, size, datatype: matrix._datatype }); } function _setsubset(matrix, index, submatrix, defaultValue) { // check index if (!index || index.isIndex !== true) { throw new TypeError('Invalid index'); } // get index size and check whether the index contains a single value var iSize = index.size(); var isScalar = index.isScalar(); // calculate the size of the submatrix, and convert it into an Array if needed var sSize; if (isMatrix(submatrix)) { // submatrix size sSize = submatrix.size(); // use array representation submatrix = submatrix.toArray(); } else { // get submatrix size (array, scalar) sSize = arraySize(submatrix); } // check index is a scalar if (isScalar) { // verify submatrix is a scalar if (sSize.length !== 0) { throw new TypeError('Scalar expected'); } // set value matrix.set(index.min(), submatrix, defaultValue); } else { // validate dimensions, index size must be one or two dimensions if (iSize.length !== 1 && iSize.length !== 2) { throw new DimensionError(iSize.length, matrix._size.length, '<'); } // check submatrix and index have the same dimensions if (sSize.length < iSize.length) { // calculate number of missing outer dimensions var i = 0; var outer = 0; while (iSize[i] === 1 && sSize[i] === 1) { i++; } while (iSize[i] === 1) { outer++; i++; } // unsqueeze both outer and inner dimensions submatrix = unsqueeze(submatrix, iSize.length, outer, sSize); } // check whether the size of the submatrix matches the index size if (!deepStrictEqual(iSize, sSize)) { throw new DimensionError(iSize, sSize, '>'); } // insert the sub matrix if (iSize.length === 1) { // if the replacement index only has 1 dimension, go trough each one and set its value var range = index.dimension(0); range.forEach(function (dataIndex, subIndex) { validateIndex(dataIndex); matrix.set([dataIndex, 0], submatrix[subIndex[0]], defaultValue); }); } else { // if the replacement index has 2 dimensions, go through each one and set the value in the correct index var firstDimensionRange = index.dimension(0); var secondDimensionRange = index.dimension(1); firstDimensionRange.forEach(function (firstDataIndex, firstSubIndex) { validateIndex(firstDataIndex); secondDimensionRange.forEach(function (secondDataIndex, secondSubIndex) { validateIndex(secondDataIndex); matrix.set([firstDataIndex, secondDataIndex], submatrix[firstSubIndex[0]][secondSubIndex[0]], defaultValue); }); }); } } return matrix; } /** * Get a single element from the matrix. * @memberof SparseMatrix * @param {number[]} index Zero-based index * @return {*} value */ SparseMatrix.prototype.get = function (index) { if (!isArray(index)) { throw new TypeError('Array expected'); } if (index.length !== this._size.length) { throw new DimensionError(index.length, this._size.length); } // check it is a pattern matrix if (!this._values) { throw new Error('Cannot invoke get on a Pattern only matrix'); } // row and column var i = index[0]; var j = index[1]; // check i, j are valid validateIndex(i, this._size[0]); validateIndex(j, this._size[1]); // find value index var k = _getValueIndex(i, this._ptr[j], this._ptr[j + 1], this._index); // check k is prior to next column k and it is in the correct row if (k < this._ptr[j + 1] && this._index[k] === i) { return this._values[k]; } return 0; }; /** * Replace a single element in the matrix. * @memberof SparseMatrix * @param {number[]} index Zero-based index * @param {*} v * @param {*} [defaultValue] Default value, filled in on new entries when * the matrix is resized. If not provided, * new matrix elements will be set to zero. * @return {SparseMatrix} self */ SparseMatrix.prototype.set = function (index, v, defaultValue) { if (!isArray(index)) { throw new TypeError('Array expected'); } if (index.length !== this._size.length) { throw new DimensionError(index.length, this._size.length); } // check it is a pattern matrix if (!this._values) { throw new Error('Cannot invoke set on a Pattern only matrix'); } // row and column var i = index[0]; var j = index[1]; // rows & columns var rows = this._size[0]; var columns = this._size[1]; // equal signature to use var eq = equalScalar; // zero value var zero = 0; if (isString(this._datatype)) { // find signature that matches (datatype, datatype) eq = typed.find(equalScalar, [this._datatype, this._datatype]) || equalScalar; // convert 0 to the same datatype zero = typed.convert(0, this._datatype); } // check we need to resize matrix if (i > rows - 1 || j > columns - 1) { // resize matrix _resize(this, Math.max(i + 1, rows), Math.max(j + 1, columns), defaultValue); // update rows & columns rows = this._size[0]; columns = this._size[1]; } // check i, j are valid validateIndex(i, rows); validateIndex(j, columns); // find value index var k = _getValueIndex(i, this._ptr[j], this._ptr[j + 1], this._index); // check k is prior to next column k and it is in the correct row if (k < this._ptr[j + 1] && this._index[k] === i) { // check value != 0 if (!eq(v, zero)) { // update value this._values[k] = v; } else { // remove value from matrix _remove(k, j, this._values, this._index, this._ptr); } } else { if (!eq(v, zero)) { // insert value @ (i, j) _insert(k, i, j, v, this._values, this._index, this._ptr); } } return this; }; function _getValueIndex(i, top, bottom, index) { // check row is on the bottom side if (bottom - top === 0) { return bottom; } // loop rows [top, bottom[ for (var r = top; r < bottom; r++) { // check we found value index if (index[r] === i) { return r; } } // we did not find row return top; } function _remove(k, j, values, index, ptr) { // remove value @ k values.splice(k, 1); index.splice(k, 1); // update pointers for (var x = j + 1; x < ptr.length; x++) { ptr[x]--; } } function _insert(k, i, j, v, values, index, ptr) { // insert value values.splice(k, 0, v); // update row for k index.splice(k, 0, i); // update column pointers for (var x = j + 1; x < ptr.length; x++) { ptr[x]++; } } /** * Resize the matrix to the given size. Returns a copy of the matrix when * `copy=true`, otherwise return the matrix itself (resize in place). * * @memberof SparseMatrix * @param {number[] | Matrix} size The new size the matrix should have. * Since sparse matrices are always two-dimensional, * size must be two numbers in either an array or a matrix * @param {*} [defaultValue=0] Default value, filled in on new entries. * If not provided, the matrix elements will * be filled with zeros. * @param {boolean} [copy] Return a resized copy of the matrix * * @return {Matrix} The resized matrix */ SparseMatrix.prototype.resize = function (size, defaultValue, copy) { // validate arguments if (!isCollection(size)) { throw new TypeError('Array or Matrix expected'); } // SparseMatrix input is always 2d, flatten this into 1d if it's indeed a vector var sizeArray = size.valueOf().map(value => { return Array.isArray(value) && value.length === 1 ? value[0] : value; }); if (sizeArray.length !== 2) { throw new Error('Only two dimensions matrix are supported'); } // check sizes sizeArray.forEach(function (value) { if (!isNumber(value) || !isInteger(value) || value < 0) { throw new TypeError('Invalid size, must contain positive integers ' + '(size: ' + format(sizeArray) + ')'); } }); // matrix to resize var m = copy ? this.clone() : this; // resize matrix return _resize(m, sizeArray[0], sizeArray[1], defaultValue); }; function _resize(matrix, rows, columns, defaultValue) { // value to insert at the time of growing matrix var value = defaultValue || 0; // equal signature to use var eq = equalScalar; // zero value var zero = 0; if (isString(matrix._datatype)) { // find signature that matches (datatype, datatype) eq = typed.find(equalScalar, [matrix._datatype, matrix._datatype]) || equalScalar; // convert 0 to the same datatype zero = typed.convert(0, matrix._datatype); // convert value to the same datatype value = typed.convert(value, matrix._datatype); } // should we insert the value? var ins = !eq(value, zero); // old columns and rows var r = matrix._size[0]; var c = matrix._size[1]; var i, j, k; // check we need to increase columns if (columns > c) { // loop new columns for (j = c; j < columns; j++) { // update matrix._ptr for current column matrix._ptr[j] = matrix._values.length; // check we need to insert matrix._values if (ins) { // loop rows for (i = 0; i < r; i++) { // add new matrix._values matrix._values.push(value); // update matrix._index matrix._index.push(i); } } } // store number of matrix._values in matrix._ptr matrix._ptr[columns] = matrix._values.length; } else if (columns < c) { // truncate matrix._ptr matrix._ptr.splice(columns + 1, c - columns); // truncate matrix._values and matrix._index matrix._values.splice(matrix._ptr[columns], matrix._values.length); matrix._index.splice(matrix._ptr[columns], matrix._index.length); } // update columns c = columns; // check we need to increase rows if (rows > r) { // check we have to insert values if (ins) { // inserts var n = 0; // loop columns for (j = 0; j < c; j++) { // update matrix._ptr for current column matrix._ptr[j] = matrix._ptr[j] + n; // where to insert matrix._values k = matrix._ptr[j + 1] + n; // pointer var p = 0; // loop new rows, initialize pointer for (i = r; i < rows; i++, p++) { // add value matrix._values.splice(k + p, 0, value); // update matrix._index matrix._index.splice(k + p, 0, i); // increment inserts n++; } } // store number of matrix._values in matrix._ptr matrix._ptr[c] = matrix._values.length; } } else if (rows < r) { // deletes var d = 0; // loop columns for (j = 0; j < c; j++) { // update matrix._ptr for current column matrix._ptr[j] = matrix._ptr[j] - d; // where matrix._values start for next column var k0 = matrix._ptr[j]; var k1 = matrix._ptr[j + 1] - d; // loop matrix._index for (k = k0; k < k1; k++) { // row i = matrix._index[k]; // check we need to delete value and matrix._index if (i > rows - 1) { // remove value matrix._values.splice(k, 1); // remove item from matrix._index matrix._index.splice(k, 1); // increase deletes d++; } } } // update matrix._ptr for current column matrix._ptr[j] = matrix._values.length; } // update matrix._size matrix._size[0] = rows; matrix._size[1] = columns; // return matrix return matrix; } /** * Reshape the matrix to the given size. Returns a copy of the matrix when * `copy=true`, otherwise return the matrix itself (reshape in place). * * NOTE: This might be better suited to copy by default, instead of modifying * in place. For now, it operates in place to remain consistent with * resize(). * * @memberof SparseMatrix * @param {number[]} sizes The new size the matrix should have. * Since sparse matrices are always two-dimensional, * size must be two numbers in either an array or a matrix * @param {boolean} [copy] Return a reshaped copy of the matrix * * @return {Matrix} The reshaped matrix */ SparseMatrix.prototype.reshape = function (sizes, copy) { // validate arguments if (!isArray(sizes)) { throw new TypeError('Array expected'); } if (sizes.length !== 2) { throw new Error('Sparse matrices can only be reshaped in two dimensions'); } // check sizes sizes.forEach(function (value) { if (!isNumber(value) || !isInteger(value) || value <= -2 || value === 0) { throw new TypeError('Invalid size, must contain positive integers or -1 ' + '(size: ' + format(sizes) + ')'); } }); var currentLength = this._size[0] * this._size[1]; sizes = processSizesWildcard(sizes, currentLength); var newLength = sizes[0] * sizes[1]; // m * n must not change if (currentLength !== newLength) { throw new Error('Reshaping sparse matrix will result in the wrong number of elements'); } // matrix to reshape var m = copy ? this.clone() : this; // return unchanged if the same shape if (this._size[0] === sizes[0] && this._size[1] === sizes[1]) { return m; } // Convert to COO format (generate a column index) var colIndex = []; for (var i = 0; i < m._ptr.length; i++) { for (var j = 0; j < m._ptr[i + 1] - m._ptr[i]; j++) { colIndex.push(i); } } // Clone the values array var values = m._values.slice(); // Clone the row index array var rowIndex = m._index.slice(); // Transform the (row, column) indices for (var _i = 0; _i < m._index.length; _i++) { var r1 = rowIndex[_i]; var c1 = colIndex[_i]; var flat = r1 * m._size[1] + c1; colIndex[_i] = flat % sizes[1]; rowIndex[_i] = Math.floor(flat / sizes[1]); } // Now reshaping is supposed to preserve the row-major order, BUT these sparse matrices are stored // in column-major order, so we have to reorder the value array now. One option is to use a multisort, // sorting several arrays based on some other array. // OR, we could easily just: // 1. Remove all values from the matrix m._values.length = 0; m._index.length = 0; m._ptr.length = sizes[1] + 1; m._size = sizes.slice(); for (var _i2 = 0; _i2 < m._ptr.length; _i2++) { m._ptr[_i2] = 0; } // 2. Re-insert all elements in the proper order (simplified code from SparseMatrix.prototype.set) // This step is probably the most time-consuming for (var h = 0; h < values.length; h++) { var _i3 = rowIndex[h]; var _j = colIndex[h]; var v = values[h]; var k = _getValueIndex(_i3, m._ptr[_j], m._ptr[_j + 1], m._index); _insert(k, _i3, _j, v, m._values, m._index, m._ptr); } // The value indices are inserted out of order, but apparently that's... still OK? return m; }; /** * Create a clone of the matrix * @memberof SparseMatrix * @return {SparseMatrix} clone */ SparseMatrix.prototype.clone = function () { var m = new SparseMatrix({ values: this._values ? clone(this._values) : undefined, index: clone(this._index), ptr: clone(this._ptr), size: clone(this._size), datatype: this._datatype }); return m; }; /** * Retrieve the size of the matrix. * @memberof SparseMatrix * @returns {number[]} size */ SparseMatrix.prototype.size = function () { return this._size.slice(0); // copy the Array }; /** * Create a new matrix with the results of the callback function executed on * each entry of the matrix. * @memberof SparseMatrix * @param {Function} callback The callback function is invoked with three * parameters: the value of the element, the index * of the element, and the Matrix being traversed. * @param {boolean} [skipZeros] Invoke callback function for non-zero values only. * * @return {SparseMatrix} matrix */ SparseMatrix.prototype.map = function (callback, skipZeros) { // check it is a pattern matrix if (!this._values) { throw new Error('Cannot invoke map on a Pattern only matrix'); } // matrix instance var me = this; // rows and columns var rows = this._size[0]; var columns = this._size[1]; var fastCallback = optimizeCallback(callback, me, 'map'); // invoke callback var invoke = function invoke(v, i, j) { // invoke callback return fastCallback.fn(v, [i, j], me); }; // invoke _map return _map(this, 0, rows - 1, 0, columns - 1, invoke, skipZeros); }; /** * Create a new matrix with the results of the callback function executed on the interval * [minRow..maxRow, minColumn..maxColumn]. */ function _map(matrix, minRow, maxRow, minColumn, maxColumn, callback, skipZeros) { // result arrays var values = []; var index = []; var ptr = []; // equal signature to use var eq = equalScalar; // zero value var zero = 0; if (isString(matrix._datatype)) { // find signature that matches (datatype, datatype) eq = typed.find(equalScalar, [matrix._datatype, matrix._datatype]) || equalScalar; // convert 0 to the same datatype zero = typed.convert(0, matrix._datatype); } // invoke callback var invoke = function invoke(v, x, y) { // invoke callback var value = callback(v, x, y); // check value != 0 if (!eq(value, zero)) { // store value values.push(value); // index index.push(x); } }; // loop columns for (var j = minColumn; j <= maxColumn; j++) { // store pointer to values index ptr.push(values.length); // k0 <= k < k1 where k0 = _ptr[j] && k1 = _ptr[j+1] var k0 = matrix._ptr[j]; var k1 = matrix._ptr[j + 1]; if (skipZeros) { // loop k within [k0, k1[ for (var k = k0; k < k1; k++) { // row index var i = matrix._index[k]; // check i is in range if (i >= minRow && i <= maxRow) { // value @ k invoke(matrix._values[k], i - minRow, j - minColumn); } } } else { // create a cache holding all defined values var _values = {}; for (var _k = k0; _k < k1; _k++) { var _i4 = matrix._index[_k]; _values[_i4] = matrix._values[_k]; } // loop over all rows (indexes can be unordered so we can't use that), // and either read the value or zero for (var _i5 = minRow; _i5 <= maxRow; _i5++) { var value = _i5 in _values ? _values[_i5] : 0; invoke(value, _i5 - minRow, j - minColumn); } } } // store number of values in ptr ptr.push(values.length); // return sparse matrix return new SparseMatrix({ values, index, ptr, size: [maxRow - minRow + 1, maxColumn - minColumn + 1] }); } /** * Execute a callback function on each entry of the matrix. * @memberof SparseMatrix * @param {Function} callback The callback function is invoked with three * parameters: the value of the element, the index * of the element, and the Matrix being traversed. * @param {boolean} [skipZeros] Invoke callback function for non-zero values only. * If false, the indices are guaranteed to be in order, * if true, the indices can be unordered. */ SparseMatrix.prototype.forEach = function (callback, skipZeros) { // check it is a pattern matrix if (!this._values) { throw new Error('Cannot invoke forEach on a Pattern only matrix'); } // matrix instance var me = this; // rows and columns var rows = this._size[0]; var columns = this._size[1]; var fastCallback = optimizeCallback(callback, me, 'forEach'); // loop columns for (var j = 0; j < columns; j++) { // k0 <= k < k1 where k0 = _ptr[j] && k1 = _ptr[j+1] var k0 = this._ptr[j]; var k1 = this._ptr[j + 1]; if (skipZeros) { // loop k within [k0, k1[ for (var k = k0; k < k1; k++) { // row index var i = this._index[k]; // value @ k // TODO apply a non indexed version of algorithm in case fastCallback is not optimized fastCallback.fn(this._values[k], [i, j], me); } } else { // create a cache holding all defined values var values = {}; for (var _k2 = k0; _k2 < k1; _k2++) { var _i6 = this._index[_k2]; values[_i6] = this._values[_k2]; } // loop over all rows (indexes can be unordered so we can't use that), // and either read the value or zero for (var _i7 = 0; _i7 < rows; _i7++) { var value = _i7 in values ? values[_i7] : 0; fastCallback.fn(value, [_i7, j], me); } } } }; /** * Iterate over the matrix elements, skipping zeros * @return {Iterable<{ value, index: number[] }>} */ SparseMatrix.prototype[Symbol.iterator] = function* () { if (!this._values) { throw new Error('Cannot iterate a Pattern only matrix'); } var columns = this._size[1]; for (var j = 0; j < columns; j++) { var k0 = this._ptr[j]; var k1 = this._ptr[j + 1]; for (var k = k0; k < k1; k++) { // row index var i = this._index[k]; yield { value: this._values[k], index: [i, j] }; } } }; /** * Create an Array with a copy of the data of the SparseMatrix * @memberof SparseMatrix * @returns {Array} array */ SparseMatrix.prototype.toArray = function () { return _toArray(this._values, this._index, this._ptr, this._size, true); }; /** * Get the primitive value of the SparseMatrix: a two dimensions array * @memberof SparseMatrix * @returns {Array} array */ SparseMatrix.prototype.valueOf = function () { return _toArray(this._values, this._index, this._ptr, this._size, false); }; function _toArray(values, index, ptr, size, copy) { // rows and columns var rows = size[0]; var columns = size[1]; // result var a = []; // vars var i, j; // initialize array for (i = 0; i < rows; i++) { a[i] = []; for (j = 0; j < columns; j++) { a[i][j] = 0; } } // loop columns for (j = 0; j < columns; j++) { // k0 <= k < k1 where k0 = _ptr[j] && k1 = _ptr[j+1] var k0 = ptr[j]; var k1 = ptr[j + 1]; // loop k within [k0, k1[ for (var k = k0; k < k1; k++) { // row index i = index[k]; // set value (use one for pattern matrix) a[i][j] = values ? copy ? clone(values[k]) : values[k] : 1; } } return a; } /** * Get a string representation of the matrix, with optional formatting options. * @memberof SparseMatrix * @param {Object | number | Function} [options] Formatting options. See * lib/utils/number:format for a * description of the available * options. * @returns {string} str */ SparseMatrix.prototype.format = function (options) { // rows and columns var rows = this._size[0]; var columns = this._size[1]; // density var density = this.density(); // rows & columns var str = 'Sparse Matrix [' + format(rows, options) + ' x ' + format(columns, options) + '] density: ' + format(density, options) + '\n'; // loop columns for (var j = 0; j < columns; j++) { // k0 <= k < k1 where k0 = _ptr[j] && k1 = _ptr[j+1] var k0 = this._ptr[j]; var k1 = this._ptr[j + 1]; // loop k within [k0, k1[ for (var k = k0; k < k1; k++) { // row index var i = this._index[k]; // append value str += '\n (' + format(i, options) + ', ' + format(j, options) + ') ==> ' + (this._values ? format(this._values[k], options) : 'X'); } } return str; }; /** * Get a string representation of the matrix * @memberof SparseMatrix * @returns {string} str */ SparseMatrix.prototype.toString = function () { return format(this.toArray()); }; /** * Get a JSON representation of the matrix * @memberof SparseMatrix * @returns {Object} */ SparseMatrix.prototype.toJSON = function () { return { mathjs: 'SparseMatrix', values: this._values, index: this._index, ptr: this._ptr, size: this._size, datatype: this._datatype }; }; /** * Get the kth Matrix diagonal. * * @memberof SparseMatrix * @param {number | BigNumber} [k=0] The kth diagonal where the vector will retrieved. * * @returns {Matrix} The matrix vector with the diagonal values. */ SparseMatrix.prototype.diagonal = function (k) { // validate k if any if (k) { // convert BigNumber to a number if (isBigNumber(k)) { k = k.toNumber(); } // is must be an integer if (!isNumber(k) || !isInteger(k)) { throw new TypeError('The parameter k must be an integer number'); } } else { // default value k = 0; } var kSuper = k > 0 ? k : 0; var kSub = k < 0 ? -k : 0; // rows & columns var rows = this._size[0]; var columns = this._size[1]; // number diagonal values var n = Math.min(rows - kSub, columns - kSuper); // diagonal arrays var values = []; var index = []; var ptr = []; // initial ptr value ptr[0] = 0; // loop columns for (var j = kSuper; j < columns && values.length < n; j++) { // k0 <= k < k1 where k0 = _ptr[j] && k1 = _ptr[j+1] var k0 = this._ptr[j]; var k1 = this._ptr[j + 1]; // loop x within [k0, k1[ for (var x = k0; x < k1; x++) { // row index var i = this._index[x]; // check row if (i === j - kSuper + kSub) { // value on this column values.push(this._values[x]); // store row index[values.length - 1] = i - kSub; // exit loop break; } } } // close ptr ptr.push(values.length); // return matrix return new SparseMatrix({ values, index, ptr, size: [n, 1] }); }; /** * Generate a matrix from a JSON object * @memberof SparseMatrix * @param {Object} json An object structured like * `{"mathjs": "SparseMatrix", "values": [], "index": [], "ptr": [], "size": []}`, * where mathjs is optional * @returns {SparseMatrix} */ SparseMatrix.fromJSON = function (json) { return new SparseMatrix(json); }; /** * Create a diagonal matrix. * * @memberof SparseMatrix * @param {Array} size The matrix size. * @param {number | Array | Matrix } value The values for the diagonal. * @param {number | BigNumber} [k=0] The kth diagonal where the vector will be filled in. * @param {number} [defaultValue] The default value for non-diagonal * @param {string} [datatype] The Matrix datatype, values must be of this datatype. * * @returns {SparseMatrix} */ SparseMatrix.diagonal = function (size, value, k, defaultValue, datatype) { if (!isArray(size)) { throw new TypeError('Array expected, size parameter'); } if (size.length !== 2) { throw new Error('Only two dimensions matrix are supported'); } // map size & validate size = size.map(function (s) { // check it is a big number if (isBigNumber(s)) { // convert it s = s.toNumber(); } // validate arguments if (!isNumber(s) || !isInteger(s) || s < 1) { throw new Error('Size values must be positive integers'); } return s; }); // validate k if any if (k) { // convert BigNumber to a number if (isBigNumber(k)) { k = k.toNumber(); } // is must be an integer if (!isNumber(k) || !isInteger(k)) { throw new TypeError('The parameter k must be an integer number'); } } else { // default value k = 0; } // equal signature to use var eq = equalScalar; // zero value var zero = 0; if (isString(datatype)) { // find signature that matches (datatype, datatype) eq = typed.find(equalScalar, [datatype, datatype]) || equalScalar; // convert 0 to the same datatype zero = typed.convert(0, datatype); } var kSuper = k > 0 ? k : 0; var kSub = k < 0 ? -k : 0; // rows and columns var rows = size[0]; var columns = size[1]; // number of non-zero items var n = Math.min(rows - kSub, columns - kSuper); // value extraction function var _value; // check value if (isArray(value)) { // validate array if (value.length !== n) { // number of values in array must be n throw new Error('Invalid value array length'); } // define function _value = function _value(i) { // return value @ i return value[i]; }; } else if (isMatrix(value)) { // matrix size var ms = value.size(); // validate matrix if (ms.length !== 1 || ms[0] !== n) { // number of values in array must be n throw new Error('Invalid matrix length'); } // define function _value = function _value(i) { // return value @ i return value.get([i]); }; } else { // define function _value = function _value() { // return value return value; }; } // create arrays var values = []; var index = []; var ptr = []; // loop items for (var j = 0; j < columns; j++) { // number of rows with value ptr.push(values.length); // diagonal index var i = j - kSuper; // check we need to set diagonal value if (i >= 0 && i < n) { // get value @ i var v = _value(i); // check for zero if (!eq(v, zero)) { // column index.push(i + kSub); // add value values.push(v); } } } // last value should be number of values ptr.push(values.length); // create SparseMatrix return new SparseMatrix({ values, index, ptr, size: [rows, columns] }); }; /** * Swap rows i and j in Matrix. * * @memberof SparseMatrix * @param {number} i Matrix row index 1 * @param {number} j Matrix row index 2 * * @return {Matrix} The matrix reference */ SparseMatrix.prototype.swapRows = function (i, j) { // check index if (!isNumber(i) || !isInteger(i) || !isNumber(j) || !isInteger(j)) { throw new Error('Row index must be positive integers'); } // check dimensions if (this._size.length !== 2) { throw new Error('Only two dimensional matrix is supported'); } // validate index validateIndex(i, this._size[0]); validateIndex(j, this._size[0]); // swap rows SparseMatrix._swapRows(i, j, this._size[1], this._values, this._index, this._ptr); // return current instance return this; }; /** * Loop rows with data in column j. * * @param {number} j Column * @param {Array} values Matrix values * @param {Array} index Matrix row indeces * @param {Array} ptr Matrix column pointers * @param {Function} callback Callback function invoked for every row in column j */ SparseMatrix._forEachRow = function (j, values, index, ptr, callback) { // indeces for column j var k0 = ptr[j]; var k1 = ptr[j + 1]; // loop for (var k = k0; k < k1; k++) { // invoke callback callback(index[k], values[k]); } }; /** * Swap rows x and y in Sparse Matrix data structures. * * @param {number} x Matrix row index 1 * @param {number} y Matrix row index 2 * @param {number} columns Number of columns in matrix * @param {Array} values Matrix values * @param {Array} index Matrix row indeces * @param {Array} ptr Matrix column pointers */ SparseMatrix._swapRows = function (x, y, columns, values, index, ptr) { // loop columns for (var j = 0; j < columns; j++) { // k0 <= k < k1 where k0 = _ptr[j] && k1 = _ptr[j+1] var k0 = ptr[j]; var k1 = ptr[j + 1]; // find value index @ x var kx = _getValueIndex(x, k0, k1, index); // find value index @ x var ky = _getValueIndex(y, k0, k1, index); // check both rows exist in matrix if (kx < k1 && ky < k1 && index[kx] === x && index[ky] === y) { // swap values (check for pattern matrix) if (values) { var v = values[kx]; values[kx] = values[ky]; values[ky] = v; } // next column continue; } // check x row exist & no y row if (kx < k1 && index[kx] === x && (ky >= k1 || index[ky] !== y)) { // value @ x (check for pattern matrix) var vx = values ? values[kx] : undefined; // insert value @ y index.splice(ky, 0, y); if (values) { values.splice(ky, 0, vx); } // remove value @ x (adjust array index if needed) index.splice(ky <= kx ? kx + 1 : kx, 1); if (values) { values.splice(ky <= kx ? kx + 1 : kx, 1); } // next column continue; } // check y row exist & no x row if (ky < k1 && index[ky] === y && (kx >= k1 || index[kx] !== x)) { // value @ y (check for pattern matrix) var vy = values ? values[ky] : undefined; // insert value @ x index.splice(kx, 0, x); if (values) { values.splice(kx, 0, vy); } // remove value @ y (adjust array index if needed) index.splice(kx <= ky ? ky + 1 : ky, 1); if (values) { values.splice(kx <= ky ? ky + 1 : ky, 1); } } } }; return SparseMatrix; }, { isClass: true });