FIX: rounding issue might appear when summing up all the decimals

This commit is contained in:
Régis Hanol 2015-11-30 11:24:25 +01:00
parent 96cd36e86d
commit 08ae5f89bd

View File

@ -1,9 +1,15 @@
// stolen from http://stackoverflow.com/a/13484088/11983
function sumsUpTo100(percentages) {
return percentages.map(p => Math.floor(p)).reduce((a, b) => a + b) === 100;
}
export default (percentages) => {
const sumOfDecimals = Math.ceil(percentages.map(a => a % 1).reduce((a, b) => a + b));
// compensate error by adding 1 to the first n items
for (let i = 0; i < sumOfDecimals; i++) {
percentages[i] = ++percentages[i];
// quit early when there is a rounding issue
if (sumsUpTo100(percentages)) break;
}
return percentages.map(a => Math.floor(a));
return percentages.map(p => Math.floor(p));
};