How to find the highest value for a column nested in JSON?

Question

I want to find the maximum value in a JSON object. This is my data-

(3) [{…}, {…}, {…}]
0: {name: "a", value: 12}
1: {name: "b", value: 28}
2: {name: "c", value: 60}

I'd like to get the maximum value, but they're nested. I could do something like this

arr = {}    
for (x in jsonObj){
  arr.push(x.value)
}    
d3.max(arr)

I was curious if there's a better way of dealing with this situation. My goal is to use d3.max() to find the highest value.

Answer 1

尽管Hrishi和Nina Scholz的其他答案都很好，但我想提一下使用D3的惯用方式是利用d3.max()。您可以传入一个访问器函数作为第二个参数，该参数将为数组的每个成员调用，并返回您感兴趣的嵌套值。

const data = [
  {name: "a", value: 12},
  {name: "b", value: 28},
  {name: "c", value: 60}
];

const maxValue = d3.max(data, d => d.value);
      // accessor function ---^

console.log(maxValue);  // 60

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