数据处理

Question

我一直在寻找一种处理数据的方法。我尝试过数组、对象和JSON.stringify()，但是我似乎无法成功地使用thoose。

我需要一个代码来处理这类数据。

first object:
first data {lesson: "MATH", count: 6}
second data {lesson: "BIOLOGY", count: 4}

second object:
first data {lesson: "MATH", average: 85, period: 1}
second data {lesson: "BIOLOGY", average: 40, period: 1}

third object
first data {lesson: "MATH", average: 95, period: 2}
second data {lesson: "BIOLOGY", average: 45, period: 2}

我需要两个函数来用给定的数据填充对象，并在需要时调用它们，如

   function reqDataAverage(lesson, period) {
   //some stuff todo
   return average;
}
   function reqDataCount(lesson) {
   //some stuff todo
   return count;
}

我用这段代码创建数据(注意:元素是“第一个数据”)。

var element = new Object();
var x;
console.log("Start of data");
for (x in TArrayI) {
    var first = TArrayI[x][0];
    var second = TArrayI[x][averageRow];
    if (first == "") {
        break;
    } else {
        element.lesson = first;
        element.average = second;
        element.period = 1;
        console.log("Lesson is " + element.lesson + "and average is " + element.average + "/" + element.period);
    }
}

在完成之后，我必须要做这样的事情：

var lessons = [...]
var result = 0;
var sum;
    function math() {
    var x;
        for (x in lessons) {
    var lesson = lessons[x];
    var averageOfThis = reqDataAverage(lesson, 1);
    var multiplierCount = reqDataCount(lesson);
    var result = result + (averageOfThis x multiplierCount);
       }
       var sum = result / 40;
    }

诚挚的问候

Answer 1

我想我明白你要什么了。您需要循环使用findAndAdd()函数来填充平均值数组。

var lessons = [];

function findAndAdd(subject, period, average){
  lessons.forEach(function(lesson){
    if(lesson.subject === subject && lesson.period === period){
      lesson.averages.push(average);
    }
  });
  return -1;
}

function Lesson(subject, period){
  this.subject = subject;
  this.period = period;
  this.averages = [];
}

function count(subject, period){
  var cnt = -1;
  lessons.forEach(function(lesson){
    if(lesson.subject === subject && lesson.period === period){
      cnt = lesson.averages.length;
    }
  });
  return cnt;
}

function average(subject, period){
  var sum, lesson;
  lessons.forEach(function(lsn){
    if(lsn.subject === subject && lsn.period === period){
      lesson = lsn;
    }
  });
  if(lesson.averages.length > 0){
    sum = lesson.averages.reduce(function(prev, curr){
      return prev + curr;
    });
    return sum / lesson.averages.length;
  }
  return -1;
}

// sample data for testing purposes
var newObj = new Lesson('MATH', 1);
lessons.push(newObj);
newObj = new Lesson('MATH', 2);
lessons.push(newObj);
newObj = new Lesson('BIOLOGY', 1);
lessons.push(newObj);
newObj = new Lesson('BIOLOGY', 2);
lessons.push(newObj);

findAndAdd('MATH', 1, 65);
findAndAdd('MATH', 1, 75);

console.log(count('MATH', 1));
console.log(average('MATH', 2));