forked from zhurui/management
49 lines
1.2 KiB
JavaScript
49 lines
1.2 KiB
JavaScript
|
"use strict";
|
||
|
|
|
||
|
|
Object.defineProperty(exports, "__esModule", {
|
||
|
|
value: true
|
||
|
|
});
|
||
|
|
exports.default = parse;
|
||
|
|
|
||
|
|
function parse(input) {
|
||
|
|
input = input.toUpperCase();
|
||
|
|
var splitIndex = input.indexOf("P");
|
||
|
|
var mantissa, exponent;
|
||
|
|
|
||
|
|
if (splitIndex !== -1) {
|
||
|
|
mantissa = input.substring(0, splitIndex);
|
||
|
|
exponent = parseInt(input.substring(splitIndex + 1));
|
||
|
|
} else {
|
||
|
|
mantissa = input;
|
||
|
|
exponent = 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
var dotIndex = mantissa.indexOf(".");
|
||
|
|
|
||
|
|
if (dotIndex !== -1) {
|
||
|
|
var integerPart = parseInt(mantissa.substring(0, dotIndex), 16);
|
||
|
|
var sign = Math.sign(integerPart);
|
||
|
|
integerPart = sign * integerPart;
|
||
|
|
var fractionLength = mantissa.length - dotIndex - 1;
|
||
|
|
var fractionalPart = parseInt(mantissa.substring(dotIndex + 1), 16);
|
||
|
|
var fraction = fractionLength > 0 ? fractionalPart / Math.pow(16, fractionLength) : 0;
|
||
|
|
|
||
|
|
if (sign === 0) {
|
||
|
|
if (fraction === 0) {
|
||
|
|
mantissa = sign;
|
||
|
|
} else {
|
||
|
|
if (Object.is(sign, -0)) {
|
||
|
|
mantissa = -fraction;
|
||
|
|
} else {
|
||
|
|
mantissa = fraction;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
} else {
|
||
|
|
mantissa = sign * (integerPart + fraction);
|
||
|
|
}
|
||
|
|
} else {
|
||
|
|
mantissa = parseInt(mantissa, 16);
|
||
|
|
}
|
||
|
|
|
||
|
|
return mantissa * (splitIndex !== -1 ? Math.pow(2, exponent) : 1);
|
||
|
|
}
|