根据最小值重新分配一系列百分比,同时保持相对比例

时间:2013-08-14 17:42:23

标签: javascript arrays algorithm percentage

FIDDLE HERE:http://jsfiddle.net/jakelauer/5S8t8/

我需要做什么

循环一系列百分比,加起来达到100%,并将任何低于最小阈值的值设置为某个百分比,然后重新分配剩余的百分比,使它们相对于彼此仍然相同,所以整个范围仍然等于100%。

为什么吗

我正在制作饼图,我需要在饼图上显示每个值,即使它是零值,因此它仍然可以点击。这意味着我需要将低于某个阈值的值设置为更高的值,但我不想丢失较高值的相对比例,并且它们不能超过100%

详情

说我有一系列值:

var range = [190, 2453, 234, 14, 1244, 532, 0, 3, 1999];

我将这些值转换为百分比值,使得范围中的每个值都成为整个范围之和的百分比,从而产生:

[0.02849002849002849, 0.36782126255810466, 0.03508771929824561, 0.002099265257159994, 0.18653471285050233, 0.07977207977207977, 0, 0.000449842555105713, 0.2997450892187734]

我想循环遍历这些百分比,并将它们设置为最小0.02或2%。这是我到目前为止的代码:

var range = [190, 2453, 234, 14, 1244, 532, 0, 3, 1999];
var minimumPercent = 0.02;

function distributeRangeGivenMinimum(range, min) {
    var sum = 0;
    for (var i = 0; i < range.length; i++) {
        sum += range[i];
    }

    var percents = [];
    for (var i = 0; i < range.length; i++) {
        percents.push(range[i] / sum);
    }

    var amtToSubtract = 0;
    var timesUnderMin = 0;
    for (var i = 0; i < range.length; i++) {
        if (percents[i] < min) {
            amtToSubtract += (min - percents[i]);
            timesUnderMin++;
            percents[i] = min;
        }
    }

    var timesOverMin = percents.length - timesUnderMin;
    if (timesOverMin > 0) {
        for (var i = 0; i < range.length; i++) {
            if (percents[i] > min) {
                percents[i] = percents[i] - (amtToSubtract / timesOverMin);
            }
        }
    }

    return percents;
}

上述函数的问题在于,虽然它确实完成了重新分配,但如果任何值 高于最小值,则失败(例如,如果其中一个值为0.0201且最小值)在重新分配后,它们最终低于最小值,我不知道如何解决这个问题。

1 个答案:

答案 0 :(得分:0)

尝试以下操作(新部分由评论标记):

var range = [190, 2453, 234, 14, 1244, 532, 0, 3, 1999];
var minimumPercent = 0.02;

function distributeRangeGivenMinimum(range, min) {
    var sum = 0;
    for (var i = 0; i < range.length; i++) {
        sum += range[i];
    }

    var percents = [];
    for (var i = 0; i < range.length; i++) {
        percents.push(range[i] / sum);
    }

    var amtToSubtract = 0;
    var timesUnderMin = 0;
    for (var i = 0; i < range.length; i++) {
        if (percents[i] < min) {
            amtToSubtract += (min - percents[i]);
            timesUnderMin++;
            percents[i] = min;
        }
    }

    var timesOverMin = percents.length - timesUnderMin;
    // begin new section
    do {
        var prevTimesOverMin = timesOverMin;
        var distSubAmt = amtToSubtract / timesOverMin;
        for (var i = 0; i < range.length; i++) {
            if (percents[i] > min && percents[i] - distSubAmt < min) {
                amtToSubtract -= (percents[i] - min);
                timesOverMin--;
                percents[i] = min;
            }
        }
    } while (timesOverMin != prevTimesOverMin);
    // end new section

    if (timesOverMin > 0) {
        for (var i = 0; i < range.length; i++) {
            if (percents[i] > min) {
                percents[i] = percents[i] - (amtToSubtract / timesOverMin);
            }
        }
    }

    return percents;
}