94 lines
2.7 KiB
JavaScript
94 lines
2.7 KiB
JavaScript
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"use strict";
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Object.defineProperty(exports, "__esModule", {
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value: true
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});
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exports.createLog1p = void 0;
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var _factory = require("../../utils/factory.js");
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var _collection = require("../../utils/collection.js");
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var _number = require("../../utils/number.js");
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var name = 'log1p';
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var dependencies = ['typed', 'config', 'divideScalar', 'log', 'Complex'];
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var createLog1p = /* #__PURE__ */(0, _factory.factory)(name, dependencies, function (_ref) {
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var typed = _ref.typed,
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config = _ref.config,
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divideScalar = _ref.divideScalar,
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log = _ref.log,
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Complex = _ref.Complex;
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/**
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* Calculate the logarithm of a `value+1`.
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*
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* For matrices, the function is evaluated element wise.
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*
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* Syntax:
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*
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* math.log1p(x)
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* math.log1p(x, base)
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*
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* Examples:
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*
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* math.log1p(2.5) // returns 1.252762968495368
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* math.exp(math.log1p(1.4)) // returns 2.4
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*
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* math.pow(10, 4) // returns 10000
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* math.log1p(9999, 10) // returns 4
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* math.log1p(9999) / math.log(10) // returns 4
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*
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* See also:
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*
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* exp, log, log2, log10
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*
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* @param {number | BigNumber | Complex | Array | Matrix} x
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* Value for which to calculate the logarithm of `x+1`.
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* @param {number | BigNumber | Complex} [base=e]
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* Optional base for the logarithm. If not provided, the natural
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* logarithm of `x+1` is calculated.
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* @return {number | BigNumber | Complex | Array | Matrix}
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* Returns the logarithm of `x+1`
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*/
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return typed(name, {
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number: function number(x) {
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if (x >= -1 || config.predictable) {
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return (0, _number.log1p)(x);
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} else {
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// negative value -> complex value computation
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return _log1pComplex(new Complex(x, 0));
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}
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},
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Complex: _log1pComplex,
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BigNumber: function BigNumber(x) {
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var y = x.plus(1);
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if (!y.isNegative() || config.predictable) {
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return y.ln();
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} else {
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// downgrade to number, return Complex valued result
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return _log1pComplex(new Complex(x.toNumber(), 0));
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}
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},
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'Array | Matrix': function ArrayMatrix(x) {
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return (0, _collection.deepMap)(x, this);
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},
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'any, any': function anyAny(x, base) {
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// calculate logarithm for a specified base, log1p(x, base)
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return divideScalar(this(x), log(base));
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}
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});
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/**
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* Calculate the natural logarithm of a complex number + 1
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* @param {Complex} x
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* @returns {Complex}
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* @private
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*/
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function _log1pComplex(x) {
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var xRe1p = x.re + 1;
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return new Complex(Math.log(Math.sqrt(xRe1p * xRe1p + x.im * x.im)), Math.atan2(x.im, xRe1p));
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}
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});
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exports.createLog1p = createLog1p;
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