20 lines
579 B
JavaScript
20 lines
579 B
JavaScript
var nodes = require('../nodes')
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, convert = require('./convert-angle')
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, asin = require('./asin');
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/**
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* Return the arccosine of the given `value`.
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*
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* @param {Double} trigValue
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* @param {Unit} output
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* @return {Unit}
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* @api public
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*/
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module.exports = function acos(trigValue, output) {
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var output = typeof output !== 'undefined' ? output : 'deg';
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var convertedValue = convert(Math.PI / 2, output) - asin(trigValue, output).val;
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var m = Math.pow(10, 9);
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convertedValue = Math.round(convertedValue * m) / m;
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return new nodes.Unit(convertedValue, output);
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};
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