如何在与javascript中的固定总和匹配的范围内生成n个随机数？

Question

我是 javascript 新手，不知道如何解决这个问题。我有一个 88.3 的固定值，我需要 6.0 到 9.99 之间的 12 个随机数，当我将它们全部相加时，它们匹配 88.3。

到目前为止，我设法使用此代码在一个范围内生成随机数：

/**
* Returns a random number between min (inclusive) and max (exclusive)
*/
function getRandomArbitrary(min, max) {
    return Math.random() * (max - min) + min;
}

 /**
 * Returns a random integer between min (inclusive) and max (inclusive).
 * The value is no lower than min (or the next integer greater than min
 * if min isn't an integer) and no greater than max (or the next integer
 * lower than max if max isn't an integer).
 * Using Math.round() will give you a non-uniform distribution!
 */
function getRandomInt(min, max) {
    min = Math.ceil(min);
    max = Math.floor(max);
    return Math.floor(Math.random() * (max - min + 1)) + min;
}

谁能帮帮我？

Answer 1

这是实现预期结果的一种方法。

原来的解决方案是这样的：https://stackoverflow.com/a/19278621/17175441，我已对其进行了修改以解决数字范围限制。

请注意，可能有更好的方法可以做到这一点，但现在就可以了：

function generate({
  targetSum,
  numberCount,
  minNum,
  maxNum
}) {
  var r = []
  var currsum = 0
  for (var i = 0; i < numberCount; i++) {
    r[i] = Math.random() * (maxNum - minNum) + minNum
    currsum += r[i]
  }

  let clamped = 0
  let currentIndex = 0
  while (currsum !== targetSum && clamped < numberCount) {
    let currNum = r[currentIndex]
    if (currNum == minNum || currNum == maxNum) {
      currentIndex++
      if (currentIndex > numberCount - 1) currentIndex = 0
      continue
    }
    currNum += (targetSum - currsum) / 3
    if (currNum <= minNum) {
      r[currentIndex] = minNum + Math.random()
      clamped++
    } else if (currNum >= maxNum) {
      r[currentIndex] = maxNum - Math.random()
      clamped++
    } else {
      r[currentIndex] = currNum
    }
    currsum = r.reduce((p, c) => p + c)
    currentIndex++
    if (currentIndex > numberCount - 1) currentIndex = 0
  }

  if (currsum !== targetSum) {
    console.log(`\nTargetSum: ${targetSum} can't be reached with the given options`)
  }
  return r
}

const numbers = generate({
  targetSum: 88.3,
  numberCount: 12,
  minNum: 6,
  maxNum: 9.99,
})
console.log('number = ', numbers)
console.log(
  'Sum = ',
  numbers.reduce((p, c) => p + c)
)