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Javascript grouping by data from data and returning array of objects

I have 100 objects of data within an array that looks like this:
{
id: "1",
date: "2022/01/01",
name: "John",
},
{
id: "2",
date: "2022/01/02",
name: "Chris",
},
I am trying to return an array of objects by date that also returns the names.
For example:
[
{
date: "2022/01/01",
names: ["John", "Steve"...]
},
{
date: "2022/01/02",
names: ["Chris", "Rob"...]
},
]
I have tried using the reduce method:
const groupedByDate = () =>
data.reduce((itemsIterated, { date, name }) => {
if (!itemsIterated[date]) {
itemsIterated[date] = {
date,
names: [],
};
}
itemsIterated[date].names.push(name);
return itemsIterated;
}, []);
The issue is this gives me array with a key of the date and then the object with date/names but I don't know how to return just the array of objects by date.

The function groupedByDate would return an object like this -
const result = {
'2022/01/01': {
date: "2022/01/01",
names: ["John", "Steve"...]
},
'2022/01/02': {
date: "2022/01/02",
names: ["Chris", "Rob"...]
},
}
However, to retrieve it in the format you need, you would need to make use of Object.values().
Object.values(result);
/*
[
{
date: "2022/01/01",
names: ["John", "Steve"...]
},
{
date: "2022/01/02",
names: ["Chris", "Rob"...]
},
]
*/
NOTE
To learn more about Object.values() - MDN
reduce's second parameter is the initial value of the accumulator. Here, we would need to use {} instead of [] in the groupedByDate function.

Filtering array of objects against another array of objects?

customerProducts: [
{
name: "foo",
id: 123
},
{
name: "test",
id: 44
}
]
otherProducts: [
{
name: "other",
id: 44
},
{
name: "test",
id: 21
}
]
I want to iterate through customerProducts, which is an array of objects. I want to filter the customerProducts that have an ID that another array of objects, otherProducts, has. So for examople, I'd want the returned result in this case to be:
{
name: "test",
id: 44
}
since otherProducts has an id of 44.
I was thinking of mapping through otherProducts and just returning an array of IDs, then running a forEach on that but that seems like a long way of doing it.

Create an indexed Set of the values to filter by (id from otherProducts) then filter customerProducts by that Set
const customerProducts = [{name: "foo",id: 123},{name: "test",id: 44}]
const otherProducts = [{name: "other",id: 44},{name: "test",id: 21}]
const otherProductIds = new Set(otherProducts.map(({ id }) => id))
const filteredCustomerProducts = customerProducts.filter(({ id }) =>
otherProductIds.has(id))
console.info(filteredCustomerProducts)

This can be done by using array methods filter and some.
customerProducts.filter((x)=> otherProducts.some(y=> y.id === x.id));
Explanation:
filter method will call each and every element in the otherProducts array and check if the id of customerProduct is present in otherProducts for at least one element.

declare customerProducts , otherProducts as JS array variable and use JS Array filter find functions
let customerProducts = [
{
name: "foo",
id: 123
},
{
name: "test",
id: 44
}
]
let otherProducts = [
{
name: "other",
id: 44
},
{
name: "test",
id: 21
}
];
let filtered = customerProducts.filter( el => otherProducts.find( e => e.id == el.id) )
console.log(filtered);

how do i create a new object based off an array and another object?

I am trying to create a new object based off an existing array. I want to create a new object that show below
{ jack: 'jack', content: 'ocean'},
{ marie: 'marie', content: 'pond'},
{ james: 'james', content: 'fish biscuit'},
{paul: 'paul', content: 'cake'}
const words = ['jack','marie','james','paul']
const myUsers = [
{ name: 'jack', likes: 'ocean' },
{ name: 'marie', likes: 'pond' },
{ name: 'james', likes: 'fish biscuits' },
{ name: 'paul', likes: 'cake' }
]
const usersByLikes = words.map(word => {
const container = {};
container[word] = myUsers.map(user => user.name);
container.content = myUsers[0].likes;
return container;
})
I am not getting the correct object, but instead it returns a list.
[ { jack: [ 'shark', 'turtle', 'otter' ], content: 'ocean'}, { marie: [ 'shark', 'turtle', 'otter' ], content: 'ocean' },
{ james: [ 'shark', 'turtle', 'otter' ], content: 'ocean' },
{ paul: [ 'shark', 'turtle', 'otter' ], content: 'ocean'} ]

What is the role of words array? I think the below code will work.
const result = myUsers.map(user => ({
[user.name]: user.name,
content: user.likes
}));
console.log('result', result);
In case, if want to filter the users in word array then below solution will work for you.
const result = myUsers.filter(user => {
if (words.includes(user.name)) {
return ({
[user.name]: user.name,
content: user.likes
})
}
return false;
});
You can achieve your need with a single loop.

The answer #aravindan-venkatesan gave should give you the result you are looking for. However important to consider:
When using .map() javascript returns an array of the same length, with whatever transformations you told it to inside map().
If you want to create a brand new object, of your own construction. Try using .reduce(). This allows you to set an input variable, i.e: object, array or string.
Then loop over, and return exactly what you want, not a mapped version of the old array.
See here for more details:
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/reduce

json object from javascript nested array

I'm using a nested array with the following structure:
arr[0]["id"] = "example0";
arr[0]["name"] = "name0";
arr[1]["id"] = "example1";
arr[1]["name"] = "name1";
arr[2]["id"] = "example2";
arr[2]["name"] = "name2";
now I'm trying to get a nested Json Object from this array
arr{
{
id: example0,
name: name00,
},
{
id: example1,
name: name01,
},
{
id: example2,
name: name02,
}
}
I tought it would work with JSON.stringify(arr); but it doesen't :(
I would be really happy for a solution.
Thank you!

If you are starting out with an array that looks like this, where each subarray's first element is the id and the second element is the name:
const array = [["example0", "name00"], ["example1", "name01"], ["example2", "name02"]]
You first need to map it to an array of Objects.
const arrayOfObjects = array.map((el) => ({
id: el[0],
name: el[1]
}))
Then you can call JSON.stringify(arrayOfObjects) to get the JSON.

You need to make a valid array:
arr = [
{
id: 'example0',
name: 'name00',
},
{
id: 'example1',
name: 'name01',
},
{
id: 'example2',
name: 'name02',
}
];
console.log(JSON.stringify(arr));
Note that I am assigning the array to a variable here. Also, I use [] to create an array where your original code had {}.

javascript (reactJS) best way to access values in a child Array

I've got the following array:
This is an array of Users, and each User has an Attributes array.
Now I want to make a new array with users and only their attributes. Like this
users{
0: {
"phone_number",
"email"
}
}
What would be the best way to achieve this?
thanks

If you need Array of users which contains arrays with users attributes, then you can use Array.prototype.map method:
let users = [
{ Attributes: [ { Name: 'phone_number' }, { Name: 'email' } ] },
{ Attributes: [ { Name: 'phone_number1' }, { Name: 'email1' } ] }
];
let result = users.map((user) => user.Attributes.map((attr) => attr.Name));
console.log(result)