simple-squiggle

diag.js (5443B)

---

 import { isMatrix } from '../../utils/is.js';
 import { arraySize } from '../../utils/array.js';
 import { isInteger } from '../../utils/number.js';
 import { factory } from '../../utils/factory.js';
 var name = 'diag';
 var dependencies = ['typed', 'matrix', 'DenseMatrix', 'SparseMatrix'];
 export var createDiag = /* #__PURE__ */factory(name, dependencies, _ref => {
   var {
     typed,
     matrix,
     DenseMatrix,
     SparseMatrix
   } = _ref;
 
   /**
    * Create a diagonal matrix or retrieve the diagonal of a matrix
    *
    * When `x` is a vector, a matrix with vector `x` on the diagonal will be returned.
    * When `x` is a two dimensional matrix, the matrixes `k`th diagonal will be returned as vector.
    * When k is positive, the values are placed on the super diagonal.
    * When k is negative, the values are placed on the sub diagonal.
    *
    * Syntax:
    *
    *     math.diag(X)
    *     math.diag(X, format)
    *     math.diag(X, k)
    *     math.diag(X, k, format)
    *
    * Examples:
    *
    *     // create a diagonal matrix
    *     math.diag([1, 2, 3])      // returns [[1, 0, 0], [0, 2, 0], [0, 0, 3]]
    *     math.diag([1, 2, 3], 1)   // returns [[0, 1, 0, 0], [0, 0, 2, 0], [0, 0, 0, 3]]
    *     math.diag([1, 2, 3], -1)  // returns [[0, 0, 0], [1, 0, 0], [0, 2, 0], [0, 0, 3]]
    *
    *    // retrieve the diagonal from a matrix
    *    const a = [[1, 2, 3], [4, 5, 6], [7, 8, 9]]
    *    math.diag(a)   // returns [1, 5, 9]
    *
    * See also:
    *
    *     ones, zeros, identity
    *
    * @param {Matrix | Array} x          A two dimensional matrix or a vector
    * @param {number | BigNumber} [k=0]  The diagonal where the vector will be filled
    *                                    in or retrieved.
    * @param {string} [format='dense']   The matrix storage format.
    *
    * @returns {Matrix | Array} Diagonal matrix from input vector, or diagonal from input matrix.
    */
   return typed(name, {
     // FIXME: simplify this huge amount of signatures as soon as typed-function supports optional arguments
     Array: function Array(x) {
       return _diag(x, 0, arraySize(x), null);
     },
     'Array, number': function ArrayNumber(x, k) {
       return _diag(x, k, arraySize(x), null);
     },
     'Array, BigNumber': function ArrayBigNumber(x, k) {
       return _diag(x, k.toNumber(), arraySize(x), null);
     },
     'Array, string': function ArrayString(x, format) {
       return _diag(x, 0, arraySize(x), format);
     },
     'Array, number, string': function ArrayNumberString(x, k, format) {
       return _diag(x, k, arraySize(x), format);
     },
     'Array, BigNumber, string': function ArrayBigNumberString(x, k, format) {
       return _diag(x, k.toNumber(), arraySize(x), format);
     },
     Matrix: function Matrix(x) {
       return _diag(x, 0, x.size(), x.storage());
     },
     'Matrix, number': function MatrixNumber(x, k) {
       return _diag(x, k, x.size(), x.storage());
     },
     'Matrix, BigNumber': function MatrixBigNumber(x, k) {
       return _diag(x, k.toNumber(), x.size(), x.storage());
     },
     'Matrix, string': function MatrixString(x, format) {
       return _diag(x, 0, x.size(), format);
     },
     'Matrix, number, string': function MatrixNumberString(x, k, format) {
       return _diag(x, k, x.size(), format);
     },
     'Matrix, BigNumber, string': function MatrixBigNumberString(x, k, format) {
       return _diag(x, k.toNumber(), x.size(), format);
     }
   });
   /**
    * Creeate diagonal matrix from a vector or vice versa
    * @param {Array | Matrix} x
    * @param {number} k
    * @param {string} format Storage format for matrix. If null,
    *                          an Array is returned
    * @returns {Array | Matrix}
    * @private
    */
 
   function _diag(x, k, size, format) {
     if (!isInteger(k)) {
       throw new TypeError('Second parameter in function diag must be an integer');
     }
 
     var kSuper = k > 0 ? k : 0;
     var kSub = k < 0 ? -k : 0; // check dimensions
 
     switch (size.length) {
       case 1:
         return _createDiagonalMatrix(x, k, format, size[0], kSub, kSuper);
 
       case 2:
         return _getDiagonal(x, k, format, size, kSub, kSuper);
     }
 
     throw new RangeError('Matrix for function diag must be 2 dimensional');
   }
 
   function _createDiagonalMatrix(x, k, format, l, kSub, kSuper) {
     // matrix size
     var ms = [l + kSub, l + kSuper];
 
     if (format && format !== 'sparse' && format !== 'dense') {
       throw new TypeError("Unknown matrix type ".concat(format, "\""));
     } // create diagonal matrix
 
 
     var m = format === 'sparse' ? SparseMatrix.diagonal(ms, x, k) : DenseMatrix.diagonal(ms, x, k); // check we need to return a matrix
 
     return format !== null ? m : m.valueOf();
   }
 
   function _getDiagonal(x, k, format, s, kSub, kSuper) {
     // check x is a Matrix
     if (isMatrix(x)) {
       // get diagonal matrix
       var dm = x.diagonal(k); // check we need to return a matrix
 
       if (format !== null) {
         // check we need to change matrix format
         if (format !== dm.storage()) {
           return matrix(dm, format);
         }
 
         return dm;
       }
 
       return dm.valueOf();
     } // vector size
 
 
     var n = Math.min(s[0] - kSub, s[1] - kSuper); // diagonal values
 
     var vector = []; // loop diagonal
 
     for (var i = 0; i < n; i++) {
       vector[i] = x[i + kSub][i + kSuper];
     } // check we need to return a matrix
 
 
     return format !== null ? matrix(vector) : vector;
   }
 });