85 lines
2.5 KiB
JavaScript
85 lines
2.5 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.createLog = 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 _index = require("../../plain/number/index.js");
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var name = 'log';
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var dependencies = ['config', 'typed', 'divideScalar', 'Complex'];
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var createLog = /* #__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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Complex = _ref.Complex;
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/**
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* Calculate the logarithm of a value.
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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.log(x)
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* math.log(x, base)
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*
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* Examples:
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*
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* math.log(3.5) // returns 1.252762968495368
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* math.exp(math.log(2.4)) // returns 2.4
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*
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* math.pow(10, 4) // returns 10000
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* math.log(10000, 10) // returns 4
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* math.log(10000) / math.log(10) // returns 4
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*
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* math.log(1024, 2) // returns 10
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* math.pow(2, 10) // returns 1024
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*
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* See also:
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*
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* exp, log2, log10, log1p
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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.
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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` is calculated.
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* @return {number | BigNumber | Complex | Array | Matrix}
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* Returns the logarithm of `x`
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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 >= 0 || config.predictable) {
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return (0, _index.logNumber)(x);
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} else {
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// negative value -> complex value computation
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return new Complex(x, 0).log();
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}
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},
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Complex: function Complex(x) {
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return x.log();
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},
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BigNumber: function BigNumber(x) {
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if (!x.isNegative() || config.predictable) {
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return x.ln();
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} else {
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// downgrade to number, return Complex valued result
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return new Complex(x.toNumber(), 0).log();
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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, log(x, base)
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return divideScalar(this(x), this(base));
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}
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});
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});
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exports.createLog = createLog;
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