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47 lines
1.5 KiB
JavaScript
47 lines
1.5 KiB
JavaScript
// units
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// load math.js
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var math = require('../index');
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/**
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* Helper function to output a value in the console. Value will be formatted.
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* @param {*} value
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*/
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function print (value) {
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var precision = 14;
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console.log(math.format(value, precision));
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}
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// units can be created by providing a value and unit name, or by providing
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// a string with a valued unit.
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console.log('create units');
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var a = math.unit(45, 'cm');
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var b = math.unit('0.1m');
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print(a); // 450 mm
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print(b); // 100 mm
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console.log();
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// units can be added, subtracted, and multiplied or divided by numbers
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console.log('perform operations');
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print(math.add(a, b)); // 0.55 m
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print(math.multiply(b, 2)); // 200 mm
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console.log();
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// units can be converted to a specific type, or to a number
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console.log('convert to another type or to a number');
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print(b.to('cm')); // 10 cm Alternatively: math.to(b, 'cm')
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print(math.to(b, 'inch')); // 3.937 inch
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print(b.toNumber('cm')); // 10
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print(math.number(b, 'gram')); // 10
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console.log();
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// the expression parser supports units too
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console.log('parse expressions');
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print(math.eval('2 inch to cm')); // 5.08 cm
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print(math.eval('cos(45 deg)')); // 0.70711
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console.log();
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// convert a unit to a number
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// A second parameter with the unit for the exported number must be provided
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print(math.eval('number(5 cm, mm)')); // Number, 50
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