I have an array that looks like this:
let arr = [
{'option1':1},{'option1':1},{'option1':1},
{'option1':2},{'option1':2},
{'option1':3},
{'option2':1},{'option2':1}
]
I need to iterate through the array and count the occurrences of each element with the same property to be displayed like this:
option1:{
1:3,
2:2,
3:1,
},
option2:{
1:2,
}
Basically saying that option1 with a property of 1 has 3 counts, option1 with a property of 2 has 2 counts, option1 with a property of 3 has 1 count and so on.
this way...
let arr =
[ { option1: 1 }, { option1: 1 }, { option1: 1 }
, { option1: 2 }, { option1: 2 }
, { option1: 3 }
, { option2: 1 }, { option2: 1 }
]
let obj = arr.reduce((r,o)=>
{
let [name,num] = Object.entries(o)[0]
if (!r[name]) r[name] = {}
if (!r[name][num]) r[name][num] = 1
else r[name][num]++
return r
},{})
console.log( obj ).as-console-wrapper { max-height: 100% !important; top: 0 }