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javascripttypescripttypeorm

An array of objects is returned to me. How to return an array of objects where only the unique groups with the maximum value will remain?

[
{"score": 99, "group":"1"},
{"score": 90, "group":"2"},
{"score":"10", "group":"1"},
{"score":"10",      "group":"2"},
]

I work with TypeOrm now and want to filter data.

Expected array:

[
{"score": 99,      "group":"1"},
{"score": 90,     "group":"2"},
]
Solution 

  • const data = [
{"score": 99, "group":"1"},
{"score": 90, "group":"2"},
{"score": 10, "group":"1"},
{"score": 10, "group":"2"}]

const result = [...new Set(data.map(i=>i.group))] // get unique group ids
  .map(g=>data.filter(({group})=>g===group) // find members of each group 
  .sort(({score:a},{score:b})=>a-b).pop()) // find the one with highest score

console.log(result)

    If your data includes scores that are strings instead of numbers, change a-b to (+a)-(+b) to coerce the strings to numbers.