数据挖掘及应用测验（一）代码版答案.js

数据挖掘及应用测验（一）代码版答案.js

var list = [10,12,14,15,17,18,18,23,25,25,25,25,26,26,33,37,37,39,39,39,39,40,40,43,45,51,80];
console.log('currently compute base on the list:' + list);

list = list.sort();
var length = list.length;
console.log('list length:' + length);

var itemCounts = {}, sum = 0, zongsu = [];

for (var idx=0; idx < length; idx ++) {
    var item = list[idx];
    sum += item;
    if (itemCounts.hasOwnProperty(item)) {
        itemCounts[item].push(item);
    } else {
        itemCounts[item] = [item];
    }
}

for (var item in itemCounts) {
    var itemList = itemCounts[item];
    zongsu.push({
        length: itemList.length,
        value: itemList[0]
    });
}

console.log('sum:' + sum);
console.log('average:' + sum / length);


zongsu = zongsu.sort(function (x, y) {return y.length - x.length});

var zongsuSize = zongsu[0].length;
for (var idx = 0; idx < zongsu.length; idx ++) {
    var item = zongsu[idx];
    if (item.length != zongsuSize) {
        break;
    }
    console.log('zongsu:' + item.value);
}

var middleIdx = parseInt(length / 2);
if (length % 2) {
    var zhongWeiShuSum = list[middleIdx - 1] + list[middleIdx];
    console.log('zhongweishu:' + zhongWeiShuSum / 2);
} else {
    console.log('zhongweishu:' + list[middleIdx - 1]);
}

var maxNumber = Math.max.apply(null, list),
    minNumber = Math.min.apply(null, list);
console.log('zhonglieshu:' + (minNumber + maxNumber) /2 );

console.log('Q1:' + list[parseInt((length + 1) * 0.25) - 1]);
console.log('Q2:' + list[parseInt((length + 1) * 0.5) - 1]);
console.log('Q3:' + list[parseInt((length + 1) * 0.75) - 1]);

var formatToOne = function (number) {
    console.log('Format %d to [0.0, 1.0] space:' + (number - minNumber) / (maxNumber - minNumber), number);
};
formatToOne(33);

var sperateBox = function (boxNumber) {
    var numberOfOneBox = parseInt(length / boxNumber), cutIdx = 0;
    for (var idx = 0;idx < boxNumber; idx ++) {
        var box = list.slice(cutIdx, cutIdx + numberOfOneBox),
            boxSum = 0;
        cutIdx += numberOfOneBox;
        for (var jdx = 0; jdx < box.length; jdx ++) {
            boxSum += box[jdx];
        }
        console.log('box %d value is:[%d...]', idx + 1, boxSum / box.length);
    }
};

sperateBox(3);

var listA = [12, 11, 32, 9],
    listB = [20, 35, 0, 8];

var computeDistance = function (objectA, objectB) {
    var distance = 0, mDistance = 0, gaps = [];
    for (var idx = 0; idx < objectA.length; idx ++) {
        var gap = Math.abs(objectA[idx] - objectB[idx]);
        distance += gap * gap;
        mDistance += gap;
        gaps.push(gap);
    }
    console.log('o distance:' + Math.sqrt(distance));
    console.log('m distance:' + mDistance);
    console.log('shang que jie distance:' + Math.max.apply(null, gaps));
};
computeDistance(listA, listB);