I need to find the total combined age of all pets in this array. I have tried this code but get a NaN output. how do i access age of pets to get the sum?
I tried this code but get a NaN output.
const totalAgeAllPets = data.reduce((result, pet) => {
return result pet.pets.age},0)
console.log(totalAgeAllPets)
const data = [{
name: "mark",
age: 27,
from: "Chicago",
pets: [],
},
{
name: "greg",
age: 68,
from: "Auburn",
pets: [{
type: "rock",
name: "herbert",
age: 126003219,
}, ],
},
{
name: "ken",
age: 28,
from: "Naperville",
pets: [{
type: "cat",
name: "colby",
age: 1,
},
{
type: "dog",
name: "charlie",
age: 3,
},
{
type: "dog",
name: "william riker",
age: 1,
},
{
type: "dog",
name: "thomas riker",
age: 1,
},
],
},
{
name: "kristiana",
age: 47,
from: "Chicago",
pets: [],
},
{
name: "bryan",
age: 27,
from: "Lincoln Park Zoo",
pets: [{
type: "white tiger",
name: "arthur",
age: 3,
},
{
type: "silverback gorilla",
name: "tommy",
age: 4,
},
{
type: "guinea pig",
name: "kirk",
age: 1,
},
{
type: "hamster",
name: "spock",
age: 1,
},
{
type: "hamster",
name: "sarek",
age: 1,
},
{
type: "cat",
name: "quark",
age: 1,
},
{
type: "cat",
name: "kira nerys",
age: 1,
},
],
},
{
name: "anthony",
age: 31,
from: "Phoenix",
pets: [],
},
{
name: "stephanie",
age: 27,
from: "Chicago",
pets: [{
type: "dog",
name: "midnight",
age: 3,
}, ],
},
{
name: "david p",
age: 40,
from: "Lancaster",
pets: [{
type: "dog",
name: "quinn",
age: 8,
}, ],
},
{
name: "patrick",
age: 39,
from: "Poway",
pets: [{
type: "dog",
name: "hazel",
age: 7,
},
{
type: "cat",
name: "fredy perlman",
age: 13,
},
],
},
{
name: "david a",
age: 32,
from: "San Francisco",
pets: [{
type: "monstera",
name: "holey",
age: 1,
}, ],
},
{
name: "timm",
age: 32,
from: "Gainsville",
pets: [{
type: "goldfish",
name: "betsy",
age: 4,
}, ],
},
{
name: "conrad",
age: 101,
from: "Minneapolis",
pets: [],
},
{
name: "nate",
age: 14,
from: "Boston",
pets: [{
type: "cat",
name: "rosie",
age: 0.005,
},
{
type: "hermit crab",
name: "kermit",
age: 1, // 16 wow wtf
},
{
type: "dog",
name: "ernie",
age: 4,
},
{
type: "cat",
name: "kendrick lamar jr",
age: 6,
},
{
type: "cat",
name: "guinan",
age: 589,
},
{
type: "cat",
name: "beverly",
age: 1,
},
],
},
{
name: "temo",
age: 25,
from: "Osaka",
pets: [{
type: "dog",
name: "nacho",
age: 1,
},
{
type: "dog",
name: "belky",
age: 1,
},
{
type: "dog",
name: "janeway",
age: 4,
},
{
type: "dog",
name: "jean-luc",
age: 12,
},
{
type: "monkey",
name: "shin chan",
age: 1,
},
],
},
{
name: "griffin",
age: 22,
from: "Chicago",
pets: [{
type: "bearded dragon",
name: "ferg",
age: 3,
}, ],
},
{
name: "eman",
age: 20,
from: "Lake in the Hills",
pets: [{
type: "parakeet",
name: "sunny",
age: 400,
},
{
type: "parrot",
name: "vic fontaine",
age: 46,
},
{
type: "parrot",
name: "worf",
age: 48,
},
{
type: "cockatoo",
name: "spockatoo",
age: 33,
},
],
},
{
name: "jürgen",
age: 28,
from: "Chicago",
pets: [{
type: "cat",
name: "mija",
age: 6,
}, ],
},
{
name: "michele",
age: 33,
from: "Rome",
pets: [{
type: "cat",
name: "caesar", // "cheeto"
age: 3,
},
{
type: "cat",
name: "cleopatra",
age: 3,
},
{
type: "cat",
name: "tuvok",
age: 10,
},
{
type: "turtle",
name: "spock",
age: 13,
},
],
},
{
name: "mitchell",
age: 19,
from: "Iowa City",
pets: [{
type: "cat",
name: "eddie",
age: 7,
}, ],
},
{
name: "reuben",
age: 41,
from: "Durham",
pets: [{
type: "cat",
name: "nico",
age: 15,
},
{
type: "cat",
name: "rocky",
age: 5,
},
],
},
{
name: "fatima",
age: 24,
from: "Milwaukee",
pets: [{
type: "snake",
name: "reginald",
age: 12,
}, ],
},
];
const totalAgeAllPets = data.reduce((result, pet) => {
return result pet.pets.age;
}, 0);
console.log(totalAgeAllPets);can someone point me in the right direction?
CodePudding user response：
Each object in data array has also nested array pets, So you have to count sum of nested array and add it in global count as:
const totalAgeAllPets = data.reduce((result, pet) => {
return result pet.pets.reduce((a, p) => a p.age, 0);
}, 0);
console.log(totalAgeAllPets);
const data = [{
name: "mark",
age: 27,
from: "Chicago",
pets: [],
},
{
name: "greg",
age: 68,
from: "Auburn",
pets: [{
type: "rock",
name: "herbert",
age: 126003219,
}, ],
},
{
name: "ken",
age: 28,
from: "Naperville",
pets: [{
type: "cat",
name: "colby",
age: 1,
},
{
type: "dog",
name: "charlie",
age: 3,
},
{
type: "dog",
name: "william riker",
age: 1,
},
{
type: "dog",
name: "thomas riker",
age: 1,
},
],
},
{
name: "kristiana",
age: 47,
from: "Chicago",
pets: [],
},
{
name: "bryan",
age: 27,
from: "Lincoln Park Zoo",
pets: [{
type: "white tiger",
name: "arthur",
age: 3,
},
{
type: "silverback gorilla",
name: "tommy",
age: 4,
},
{
type: "guinea pig",
name: "kirk",
age: 1,
},
{
type: "hamster",
name: "spock",
age: 1,
},
{
type: "hamster",
name: "sarek",
age: 1,
},
{
type: "cat",
name: "quark",
age: 1,
},
{
type: "cat",
name: "kira nerys",
age: 1,
},
],
},
{
name: "anthony",
age: 31,
from: "Phoenix",
pets: [],
},
{
name: "stephanie",
age: 27,
from: "Chicago",
pets: [{
type: "dog",
name: "midnight",
age: 3,
}, ],
},
{
name: "david p",
age: 40,
from: "Lancaster",
pets: [{
type: "dog",
name: "quinn",
age: 8,
}, ],
},
{
name: "patrick",
age: 39,
from: "Poway",
pets: [{
type: "dog",
name: "hazel",
age: 7,
},
{
type: "cat",
name: "fredy perlman",
age: 13,
},
],
},
{
name: "david a",
age: 32,
from: "San Francisco",
pets: [{
type: "monstera",
name: "holey",
age: 1,
}, ],
},
{
name: "timm",
age: 32,
from: "Gainsville",
pets: [{
type: "goldfish",
name: "betsy",
age: 4,
}, ],
},
{
name: "conrad",
age: 101,
from: "Minneapolis",
pets: [],
},
{
name: "nate",
age: 14,
from: "Boston",
pets: [{
type: "cat",
name: "rosie",
age: 0.005,
},
{
type: "hermit crab",
name: "kermit",
age: 1, // 16 wow wtf
},
{
type: "dog",
name: "ernie",
age: 4,
},
{
type: "cat",
name: "kendrick lamar jr",
age: 6,
},
{
type: "cat",
name: "guinan",
age: 589,
},
{
type: "cat",
name: "beverly",
age: 1,
},
],
},
{
name: "temo",
age: 25,
from: "Osaka",
pets: [{
type: "dog",
name: "nacho",
age: 1,
},
{
type: "dog",
name: "belky",
age: 1,
},
{
type: "dog",
name: "janeway",
age: 4,
},
{
type: "dog",
name: "jean-luc",
age: 12,
},
{
type: "monkey",
name: "shin chan",
age: 1,
},
],
},
{
name: "griffin",
age: 22,
from: "Chicago",
pets: [{
type: "bearded dragon",
name: "ferg",
age: 3,
}, ],
},
{
name: "eman",
age: 20,
from: "Lake in the Hills",
pets: [{
type: "parakeet",
name: "sunny",
age: 400,
},
{
type: "parrot",
name: "vic fontaine",
age: 46,
},
{
type: "parrot",
name: "worf",
age: 48,
},
{
type: "cockatoo",
name: "spockatoo",
age: 33,
},
],
},
{
name: "jürgen",
age: 28,
from: "Chicago",
pets: [{
type: "cat",
name: "mija",
age: 6,
}, ],
},
{
name: "michele",
age: 33,
from: "Rome",
pets: [{
type: "cat",
name: "caesar", // "cheeto"
age: 3,
},
{
type: "cat",
name: "cleopatra",
age: 3,
},
{
type: "cat",
name: "tuvok",
age: 10,
},
{
type: "turtle",
name: "spock",
age: 13,
},
],
},
{
name: "mitchell",
age: 19,
from: "Iowa City",
pets: [{
type: "cat",
name: "eddie",
age: 7,
}, ],
},
{
name: "reuben",
age: 41,
from: "Durham",
pets: [{
type: "cat",
name: "nico",
age: 15,
},
{
type: "cat",
name: "rocky",
age: 5,
},
],
},
{
name: "fatima",
age: 24,
from: "Milwaukee",
pets: [{
type: "snake",
name: "reginald",
age: 12,
}, ],
},
];
const totalAgeAllPets = data.reduce((result, pet) => {
return result pet.pets.reduce((a, p) => a p.age, 0);
}, 0);
console.log(totalAgeAllPets);CodePudding user response：
One approach can be as shown below:
const data = [
{
"name": "mark",
"age": 27,
"from": "Chicago",
"pets": []
},
{
"name": "greg",
"age": 68,
"from": "Auburn",
"pets": [
{
"type": "rock",
"name": "herbert",
"age": 126003219
}
]
},
{
"name": "ken",
"age": 28,
"from": "Naperville",
"pets": [
{
"type": "cat",
"name": "colby",
"age": 1
},
{
"type": "dog",
"name": "charlie",
"age": 3
},
{
"type": "dog",
"name": "william riker",
"age": 1
},
{
"type": "dog",
"name": "thomas riker",
"age": 1
}
]
},
{
"name": "kristiana",
"age": 47,
"from": "Chicago",
"pets": []
},
{
"name": "bryan",
"age": 27,
"from": "Lincoln Park Zoo",
"pets": [
{
"type": "white tiger",
"name": "arthur",
"age": 3
},
{
"type": "silverback gorilla",
"name": "tommy",
"age": 4
},
{
"type": "guinea pig",
"name": "kirk",
"age": 1
},
{
"type": "hamster",
"name": "spock",
"age": 1
},
{
"type": "hamster",
"name": "sarek",
"age": 1
},
{
"type": "cat",
"name": "quark",
"age": 1
},
{
"type": "cat",
"name": "kira nerys",
"age": 1
}
]
},
{
"name": "anthony",
"age": 31,
"from": "Phoenix",
"pets": []
},
{
"name": "stephanie",
"age": 27,
"from": "Chicago",
"pets": [
{
"type": "dog",
"name": "midnight",
"age": 3
}
]
},
{
"name": "david p",
"age": 40,
"from": "Lancaster",
"pets": [
{
"type": "dog",
"name": "quinn",
"age": 8
}
]
},
{
"name": "patrick",
"age": 39,
"from": "Poway",
"pets": [
{
"type": "dog",
"name": "hazel",
"age": 7
},
{
"type": "cat",
"name": "fredy perlman",
"age": 13
}
]
},
{
"name": "david a",
"age": 32,
"from": "San Francisco",
"pets": [
{
"type": "monstera",
"name": "holey",
"age": 1
}
]
},
{
"name": "timm",
"age": 32,
"from": "Gainsville",
"pets": [
{
"type": "goldfish",
"name": "betsy",
"age": 4
}
]
},
{
"name": "conrad",
"age": 101,
"from": "Minneapolis",
"pets": []
},
{
"name": "nate",
"age": 14,
"from": "Boston",
"pets": [
{
"type": "cat",
"name": "rosie",
"age": 0.005
},
{
"type": "hermit crab",
"name": "kermit",
"age": 1
},
{
"type": "dog",
"name": "ernie",
"age": 4
},
{
"type": "cat",
"name": "kendrick lamar jr",
"age": 6
},
{
"type": "cat",
"name": "guinan",
"age": 589
},
{
"type": "cat",
"name": "beverly",
"age": 1
}
]
},
{
"name": "temo",
"age": 25,
"from": "Osaka",
"pets": [
{
"type": "dog",
"name": "nacho",
"age": 1
},
{
"type": "dog",
"name": "belky",
"age": 1
},
{
"type": "dog",
"name": "janeway",
"age": 4
},
{
"type": "dog",
"name": "jean-luc",
"age": 12
},
{
"type": "monkey",
"name": "shin chan",
"age": 1
}
]
},
{
"name": "griffin",
"age": 22,
"from": "Chicago",
"pets": [
{
"type": "bearded dragon",
"name": "ferg",
"age": 3
}
]
},
{
"name": "eman",
"age": 20,
"from": "Lake in the Hills",
"pets": [
{
"type": "parakeet",
"name": "sunny",
"age": 400
},
{
"type": "parrot",
"name": "vic fontaine",
"age": 46
},
{
"type": "parrot",
"name": "worf",
"age": 48
},
{
"type": "cockatoo",
"name": "spockatoo",
"age": 33
}
]
},
{
"name": "jürgen",
"age": 28,
"from": "Chicago",
"pets": [
{
"type": "cat",
"name": "mija",
"age": 6
}
]
},
{
"name": "michele",
"age": 33,
"from": "Rome",
"pets": [
{
"type": "cat",
"name": "caesar",
"age": 3
},
{
"type": "cat",
"name": "cleopatra",
"age": 3
},
{
"type": "cat",
"name": "tuvok",
"age": 10
},
{
"type": "turtle",
"name": "spock",
"age": 13
}
]
},
{
"name": "mitchell",
"age": 19,
"from": "Iowa City",
"pets": [
{
"type": "cat",
"name": "eddie",
"age": 7
}
]
},
{
"name": "reuben",
"age": 41,
"from": "Durham",
"pets": [
{
"type": "cat",
"name": "nico",
"age": 15
},
{
"type": "cat",
"name": "rocky",
"age": 5
}
]
},
{
"name": "fatima",
"age": 24,
"from": "Milwaukee",
"pets": [
{
"type": "snake",
"name": "reginald",
"age": 12
}
]
}
];
const totalAgeOfAllPets = data.reduce((acc, curr) => {
curr?.pets?.forEach(({age}) => {acc = acc age});
return acc;
}, 0);
console.log(`Total age of all pets : ${totalAgeOfAllPets}`);CodePudding user response：
Use .flatMap() to filter out all non-owners:
data.flatMap(obj => obj.pets.length > 0 ? obj.pets : [])
You'll get an array of pet objects. Next use reduce to get the sum of all pet.age
.reduce((sum, pet) => sum pet.age, 0);
const data =[{name:"mark",age:27,from:"Chicago",pets:[]},{name:"greg",age:68,from:"Auburn",pets:[{type:"rock",name:"herbert",age:126003219}]},{name:"ken",age:28,from:"Naperville",pets:[{type:"cat",name:"colby",age:1},{type:"dog",name:"charlie",age:3},{type:"dog",name:"william riker",age:1},{type:"dog",name:"thomas riker",age:1}],},{name:"kristiana",age:47,from:"Chicago",pets:[]},{name:"bryan",age:27,from:"Lincoln Park Zoo",pets:[{type:"white tiger",name:"arthur",age:3},{type:"silverback gorilla",name:"tommy",age:4},{type:"guinea pig",name:"kirk",age:1},{type:"hamster",name:"spock",age:1},{type:"hamster",name:"sarek",age:1},{type:"cat",name:"quark",age:1},{type:"cat",name:"kira nerys",age:1}]},{name:"anthony",age:31,from:"Phoenix",pets:[]},{name:"stephanie",age:27,from:"Chicago",pets:[{type:"dog",name:"midnight",age:3}]},{name:"david p",age:40,from:"Lancaster",pets:[{type:"dog",name:"quinn",age:8}]},{name:"patrick",age:39,from:"Poway",pets:[{type:"dog",name:"hazel",age:7},{type:"cat",name:"fredy perlman",age:13}]},{name:"david a",age:32,from:"San Francisco",pets:[{type:"monstera",name:"holey",age:1}]},{name:"timm",age:32,from:"Gainsville",pets:[{type:"goldfish",name:"betsy",age:4}]},{name:"conrad",age:101,from:"Minneapolis",pets:[]},{name:"nate",age:14,from:"Boston",pets:[{type:"cat",name:"rosie",age:0.005},{type:"hermit crab",name:"kermit",age:1},{type:"dog",name:"ernie",age:4},{type:"cat",name:"kendrick lamar jr",age:6},{type:"cat",name:"guinan",age:589},{type:"cat",name:"beverly",age:1}]},{name:"temo",age:25,from:"Osaka",pets:[{type:"dog",name:"nacho",age:1},{type:"dog",name:"belky",age:1},{type:"dog",name:"janeway",age:4},{type:"dog",name:"jean-luc",age:12},{type:"monkey",name:"shin chan",age:1}]},{name:"griffin",age:22,from:"Chicago",pets:[{type:"bearded dragon",name:"ferg",age:3}]},{name:"eman",age:20,from:"Lake in the Hills",pets:[{type:"parakeet",name:"sunny",age:400},{type:"parrot",name:"vic fontaine",age:46},{type:"parrot",name:"worf",age:48},{type:"cockatoo",name:"spockatoo",age:33}]},{name:"jürgen",age:28,from:"Chicago",pets:[{type:"cat",name:"mija",age:6}]},{name:"michele",age:33,from:"Rome",pets:[{type:"cat",name:"caesar",age:3},{type:"cat",name:"cleopatra",age:3},{type:"cat",name:"tuvok",age:10},{type:"turtle",name:"spock",age:13}]},{name:"mitchell",age:19,from:"Iowa City",pets:[{type:"cat",name:"eddie",age:7},]},{name:"reuben",age:41,from:"Durham",pets:[{type:"cat",name:"nico",age:15},{type:"cat",name:"rocky",age:5}]},{name:"fatima",age:24,from:"Milwaukee",pets:[{type:"snake",name:"reginald",age:12}]}];
const totalAgeAllPets = data.flatMap(obj => obj.pets.length > 0 ? obj.pets : []).reduce((sum, pet) => sum pet.age, 0);
console.log(totalAgeAllPets);