53 lines
1.7 KiB
JavaScript
53 lines
1.7 KiB
JavaScript
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/* eslint-disable no-loss-of-precision */
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// BigNumbers
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const { create, all } = require('..')
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// configure the default type of numbers as BigNumbers
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const config = {
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// Default type of number
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// Available options: 'number' (default), 'BigNumber', or 'Fraction'
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number: 'BigNumber',
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// Number of significant digits for BigNumbers
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precision: 20
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}
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const math = create(all, config)
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console.log('round-off errors with numbers')
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print(math.add(0.1, 0.2)) // number, 0.30000000000000004
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print(math.divide(0.3, 0.2)) // number, 1.4999999999999998
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console.log()
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console.log('no round-off errors with BigNumbers')
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print(math.add(math.bignumber(0.1), math.bignumber(0.2))) // BigNumber, 0.3
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print(math.divide(math.bignumber(0.3), math.bignumber(0.2))) // BigNumber, 1.5
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console.log()
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console.log('create BigNumbers from strings when exceeding the range of a number')
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print(math.bignumber(1.2e+500)) // BigNumber, Infinity WRONG
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print(math.bignumber('1.2e+500')) // BigNumber, 1.2e+500
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console.log()
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console.log('BigNumbers still have a limited precision and are no silve bullet')
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const third = math.divide(math.bignumber(1), math.bignumber(3))
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const total = math.add(third, third, third)
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print(total) // BigNumber, 0.99999999999999999999
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console.log()
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// one can work conveniently with BigNumbers using the expression parser.
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// note though that BigNumbers are only supported in arithmetic functions
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console.log('use BigNumbers in the expression parser')
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print(math.evaluate('0.1 + 0.2')) // BigNumber, 0.3
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print(math.evaluate('0.3 / 0.2')) // BigNumber, 1.5
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console.log()
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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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console.log(math.format(value))
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}
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