78 lines
2.7 KiB
JavaScript
78 lines
2.7 KiB
JavaScript
import { factory } from '../../utils/factory.js';
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var name = 'matrixFromFunction';
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var dependencies = ['typed', 'matrix', 'isZero'];
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export var createMatrixFromFunction = /* #__PURE__ */factory(name, dependencies, _ref => {
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var {
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typed,
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matrix,
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isZero
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} = _ref;
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/**
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* Create a matrix by evaluating a generating function at each index.
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* The simplest overload returns a multi-dimensional array as long as `size` is an array.
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* Passing `size` as a Matrix or specifying a `format` will result in returning a Matrix.
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*
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* Syntax:
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*
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* math.matrixFromFunction(size, fn)
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* math.matrixFromFunction(size, fn, format)
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* math.matrixFromFunction(size, fn, format, datatype)
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* math.matrixFromFunction(size, format, fn)
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* math.matrixFromFunction(size, format, datatype, fn)
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*
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* Examples:
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*
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* math.matrixFromFunction([3,3], i => i[0] - i[1]) // an antisymmetric matrix
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* math.matrixFromFunction([100, 100], 'sparse', i => i[0] - i[1] === 1 ? 4 : 0) // a sparse subdiagonal matrix
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* math.matrixFromFunction([5], i => math.random()) // a random vector
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*
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* See also:
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*
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* matrix, zeros
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*
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* @param {Array | Matrix} size The size of the matrix to be created
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* @param {function} fn Callback function invoked for every entry in the matrix
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* @param {string} [format] The Matrix storage format, either `'dense'` or `'sparse'`
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* @param {string} [datatype] Type of the values
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* @return {Array | Matrix} Returns the created matrix
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*/
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return typed(name, {
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'Array | Matrix, function, string, string': function ArrayMatrixFunctionStringString(size, fn, format, datatype) {
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return _create(size, fn, format, datatype);
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},
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'Array | Matrix, function, string': function ArrayMatrixFunctionString(size, fn, format) {
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return _create(size, fn, format);
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},
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'Matrix, function': function MatrixFunction(size, fn) {
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return _create(size, fn, 'dense');
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},
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'Array, function': function ArrayFunction(size, fn) {
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return _create(size, fn, 'dense').toArray();
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},
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'Array | Matrix, string, function': function ArrayMatrixStringFunction(size, format, fn) {
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return _create(size, fn, format);
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},
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'Array | Matrix, string, string, function': function ArrayMatrixStringStringFunction(size, format, datatype, fn) {
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return _create(size, fn, format, datatype);
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}
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});
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function _create(size, fn, format, datatype) {
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var m;
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if (datatype !== undefined) {
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m = matrix(format, datatype);
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} else {
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m = matrix(format);
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}
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m.resize(size);
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m.forEach(function (_, index) {
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var val = fn(index);
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if (isZero(val)) return;
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m.set(index, val);
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});
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return m;
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}
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}); |