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Stáhnout (1.15 KB) Statistiky
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1 3a515b92 cagy
export default function parse(input) {
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  input = input.toUpperCase();
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  var splitIndex = input.indexOf("P");
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  var mantissa, exponent;
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  if (splitIndex !== -1) {
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    mantissa = input.substring(0, splitIndex);
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    exponent = parseInt(input.substring(splitIndex + 1));
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  } else {
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    mantissa = input;
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    exponent = 0;
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  }
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  var dotIndex = mantissa.indexOf(".");
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  if (dotIndex !== -1) {
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    var integerPart = parseInt(mantissa.substring(0, dotIndex), 16);
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    var sign = Math.sign(integerPart);
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    integerPart = sign * integerPart;
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    var fractionLength = mantissa.length - dotIndex - 1;
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    var fractionalPart = parseInt(mantissa.substring(dotIndex + 1), 16);
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    var fraction = fractionLength > 0 ? fractionalPart / Math.pow(16, fractionLength) : 0;
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    if (sign === 0) {
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      if (fraction === 0) {
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        mantissa = sign;
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      } else {
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        if (Object.is(sign, -0)) {
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          mantissa = -fraction;
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        } else {
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          mantissa = fraction;
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        }
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      }
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    } else {
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      mantissa = sign * (integerPart + fraction);
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    }
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  } else {
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    mantissa = parseInt(mantissa, 16);
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  }
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  return mantissa * (splitIndex !== -1 ? Math.pow(2, exponent) : 1);
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}