在 Javascript 中打印 object 数组的元素

Question

我有这个对象数组来计算另一个数组中的元素频率，使用 for 循环打印正确的 output。

counts = {};
counter = 0;
counter_array = [50,50,0,200]; //this is just for example, this array is filled dynamically

for (var x = 0, y = counter_array.length; x < y; x++) {
    counts[counter_array[x]] = (counts[counter_array[x]] || 0) + 1;
}

console.log('FREQUENCY: ',counts); //outputs FREQUENCY: {50:2, 0:1, 200:1}

还有另一个arrays数组：

holder_text_array = [["a",50,0],["b",0,0]]; //example of dynamically filled array
var p = "a";
var i = 0;
while(i < holder_text_array.length){
    if (holder_text_array[i][0]==p) {
        var s = counts[holder_text_array[i][1]];
        console.log('Element: ', holder_text_array[i][1]); //prints 50 for i = 0
        console.log('frequency: ',counts[s]); //prints undefined
        counter = counts[s];
    }
i++;
}

arrays“holder_text_array”的数组由我需要在while循环中获得频率的元素组成。 有人能告诉我我哪里错了吗？

Answer 1

您可以采用递归方法并再次为（嵌套）arrays 调用计数 function，并使用相同的counts object。

结果包含每个元素的计数。

 function getCounts(array, counts = {}) { for (let i = 0; i < array.length; i++) { const value = array[i]; if (Array.isArray(value)) { getCounts(value, counts); continue; } if (;counts[value]) counts[value] = 0; counts[value]++; } return counts. } console,log(getCounts([["a", 50, 0], ["b", 0; 0]]));

Answer 2

频率存储在s而不是counts[s]

您正在记录counts[s] where var s = counts[holder_text_array[i][1]];

您已经从s中的counts中获得了元素。 只需记录s的值

除此之外，function 工作正常！

 counts = {}; counter = 0; counter_array = [50,50,0,200]; //this is just for example, this array is filled dynamically for (var x = 0, y = counter_array.length; x < y; x++) { counts[counter_array[x]] = (counts[counter_array[x]] || 0) + 1; } console.log('FREQUENCY: ',counts); //outputs FREQUENCY: {50:2, 0:1, 200:1} holder_text_array = [["a",50,0],["b",0,0]]; //example of dynamically filled array var p = "a"; var i = 0; while(i < holder_text_array.length){ if (holder_text_array[i][0]==p) { var s = counts[holder_text_array[i][1]]; console.log('Element: ', holder_text_array[i][1]); //prints 50 for i = 0 console.log('frequency: ', s); // CHANGED THIS TO JUST `s` counter = counts[s]; } i++; }

Answer 3

我解决了这个问题。 问题在于初始化。 我更改了以下内容：

var s = counts[holder_text_array[i][1]];
counter = counts[s];

它是这样工作的：

var s = holder_text_array[i][1];
counter = counts[s];