React - 在对象之间定义更大的字符串

Question

我正在计算数组中每个对象（团队）的平均分数。这是我的数据结构：const scores = [  { day: "1", Barcelona: 1, Real: 3, Valencia: 0 },  { day: "2", Barcelona: 4, Real: 6, Valencia: 3 },  { day: "3", Barcelona: 7, Real: 7, Valencia: 3 },  { day: "4", Barcelona: 7, Real: 8, Valencia: 6 }];这就是我计算平均值的方式const getAverage = team => {  if (isNaN(scores[0][team])) return null;  return scores.map(x => x[team]).reduce((a, c) => a + c) / scores.length;}; 我需要建立人数越多的对象队伍越强。我怎样才能做到这一点 ？实力较强的球队是平均水平较高的球队。这里我做了一个原型来重现场景：https : //codesandbox.io/s/recharts-examples-y0y7q

Answer 1

从这样的团队数组中获取 maxAverage：

this.state = {

    homeCity: "Barcelona",

    awayCity: "Valencia"

}

const scores = [

    { day: "1", Barcelona: 1, Real: 3, Valencia: 0 },

    { day: "2", Barcelona: 4, Real: 6, Valencia: 3 },

    { day: "3", Barcelona: 7, Real: 7, Valencia: 3 },

    { day: "4", Barcelona: 7, Real: 8, Valencia: 6 }

  ];

const getAverage = team => {

    if (isNaN(scores[0][team])) return null;

    return scores.map(x => x[team]).reduce((a, c) => a + c) / scores.length;

};

const maxAverage = teams => {

    return teams.map(team => {

        return {

            team:team, 

            avg: getAverage(team)

        }

    }).reduce((a,b)=>a.avg>b.avg?a:b).team

}

console.log(maxAverage([this.state.homeCity,this.state.awayCity]));

Answer 2

您可以扩展您的代码，循环遍历第一个元素以获取所有键，过滤出日期键，以便我们留下所有团队名称，映射团队名称并获取平均值然后进行排序

const scores = [

  { day: "1", Barcelona: 1, Real: 3, Valencia: 0 },

  { day: "2", Barcelona: 4, Real: 6, Valencia: 3 },

  { day: "3", Barcelona: 7, Real: 7, Valencia: 3 },

  { day: "4", Barcelona: 7, Real: 8, Valencia: 6 }

];

const getAverage = team => {

  if (isNaN(scores[0][team])) return null;

  return scores.map(x => x[team]).reduce((a, c) => a + c) / scores.length

};

let stronger = Object.entries(scores[0])

                     .filter(([key, value]) => key !== 'day')

                     .map(([key, value]) => [key, getAverage(key)])

                     .sort((a, b) => b[1] - a[1])

console.log(stronger)