math Latest (v1.1.4)

max_by

Return the maximum element in an array using the expression expr as the

max_by(elements: array, expr: expression->number | expression->string) -> any

Description

Return the maximum element in an array using the expression expr as the comparison key. The entire maximum element is returned. Below are several examples using the people array (defined above) as the given input.

Arguments

Required

Name	Type	Description
`elements`	`array`
`expr`	`expression->number, expression->string`

Returns

Type: any

Examples

Given the following JSON input:


{
  "people": [
    {
      "age": 20,
      "age_str": "20",
      "bool": true,
      "name": "a",
      "extra": "foo"
    },
    {
      "age": 40,
      "age_str": "40",
      "bool": false,
      "name": "b",
      "extra": "bar"
    },
    {
      "age": 30,
      "age_str": "30",
      "bool": true,
      "name": "c"
    },
    {
      "age": 50,
      "age_str": "50",
      "bool": false,
      "name": "d"
    },
    {
      "age": 10,
      "age_str": "10",
      "bool": true,
      "name": 3
    }
  ]
}

Expression	Result
`max_by(people, &age)`	`{"age":50,"age_str":"50","bool":false,"name":"d"}`
`max_by(people, &age_str)`	`{"age":50,"age_str":"50","bool":false,"name":"d"}`
`max_by(people, &bool)`	`ERROR: invalid-type`
`max_by(people, &extra)`	`ERROR: invalid-type`
`max_by(people, &to_number(age_str))`	`{"age":50,"age_str":"50","bool":false,"name":"d"}`
`max_by(people, &age_str)`	`ERROR: invalid-type`
`max_by(people, age)`	`ERROR: invalid-type`