I am trying to do something very simple but I can't get it to work. I have 3 variables:
abc = 123
def = 456
ghi = 789
I created array like this:
numbers = [abc, def, ghi]
Then I did this:
Math.max.apply(null, numbers)
It returned 789, then I tried to do:
numbers.indexOf(789)
but it returns 2 = index of ghi, problem is I wanna find "ghi" name exactly and I am struggling.
You need to store the labels in your array as well. JavaScript is not able to read your variable name during your program's execution:
const abc = 123;
const def = 456;
const ghi = 789;
const numbers = [
{label: 'abc', value: abc},
{label: 'def', value: def},
{label: 'ghi', value: ghi}
];
const max = Math.max.apply(null, numbers.map(v => v.value));
console.log(max);
const maxObject = numbers.find(n => n.value === max);
console.log(maxObject.label);If you use associative array then you dont need objects. here a sample solution using an array
findMax = () => {
// define the array
let array = [];
// filling items to the array
array['a'] = 123;
array['b'] = 456;
array['c'] = 789;
// variables for max and maxKey
let max = 0;
let maxKey = '';
// iterate through the assoc array
for (var key in array) {
if(max <= array[key]){
max = array[key];
maxKey = key
}
}
console.log('max key ' + maxKey + ' max value ' + max);
}<input type='button' onclick='findMax()' value='find max' />You should use Object instead of Array.
const abc = 123;
const def = 456;
const ghi = 789;
const numbers = { abc, def, ghi };
const max = Math.max.apply(null, Object.values(numbers));
const [variableName] = Object.entries(numbers).find(([el, val]) => val === max);
console.log(variableName)
Solution 👇
As you have unique labels for values, I would define your data as an object. Then you can build a simple reducer to return the label and the value together:
const numbers = {
abc: 123,
def: 456,
ghi: 789
}
const [label, value] = Object.entries(numbers).reduce((a, b) => a[1] > b[1] ? a : b)
console.log(label, value)The benefits of storing your variables in this way, is that you can quickly access your values by label simply by using numbers['abc'] for example.
