math-float-round.js 732 B

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  1. 'use strict';
  2. var sign = require('../internals/math-sign');
  3. var roundTiesToEven = require('../internals/math-round-ties-to-even');
  4. var abs = Math.abs;
  5. var EPSILON = 2.220446049250313e-16; // Number.EPSILON
  6. module.exports = function (x, FLOAT_EPSILON, FLOAT_MAX_VALUE, FLOAT_MIN_VALUE) {
  7. var n = +x;
  8. var absolute = abs(n);
  9. var s = sign(n);
  10. if (absolute < FLOAT_MIN_VALUE) return s * roundTiesToEven(absolute / FLOAT_MIN_VALUE / FLOAT_EPSILON) * FLOAT_MIN_VALUE * FLOAT_EPSILON;
  11. var a = (1 + FLOAT_EPSILON / EPSILON) * absolute;
  12. var result = a - (a - absolute);
  13. // eslint-disable-next-line no-self-compare -- NaN check
  14. if (result > FLOAT_MAX_VALUE || result !== result) return s * Infinity;
  15. return s * result;
  16. };