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How to extract numbers from an array [closed]

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So basically I have an array of ids and I want to return only a simple array which I want to look like this
*[1,2,3]*
instead of
*[0:[1] , 1:[2]]*
Is there any way to do it
Code
const usersWhoHavePurchasedYourCourses = usersWhoHaveTokens.filter(
(user1: any) => {
return user1.tokens
?.map((token: any) => parseInt(token.course_id))
.includes(user.courses?.map((course: any) => course.id));
});
The output looks like this
output
As I said I don`t want to return this kind of output.

Edit
In attempting to reverse-engineer your logic, wouldn't you want to filter by checking if a user has at least one course? I recommend using Array.prototype.some as your filter result.
const user = { courses: [{ id: 1 }, { id: 2 }] };
const usersWhoHaveTokens = [
{ id: 1, tokens: [{ course_id: '1' }] },
{ id: 2, tokens: [{ course_id: '2' }] },
{ id: 3, tokens: [{ course_id: '3' }] },
];
// Compute the set, for faster processing
const userCourseIds = new Set(user.courses.map((course) => course.id));
const usersWhoHavePurchasedYourCourses = usersWhoHaveTokens
.filter(({ tokens }) => tokens
.some((token) => userCourseIds.has(parseInt(token.course_id))))
.map(({ id }) => id);
console.log(usersWhoHavePurchasedYourCourses); // [1, 2]
Original response
If you object is an 'object' type, you will need to transform it into an array, and then flatten it.
const
obj = { 0: [1], 1: [2] },
arr = Object.values(obj).flat();
console.log(JSON.stringify(arr)); // [1, 2]
If you want to preserve indices:
const
obj = { 1: [2], 5: [6] },
arr = Object.entries(obj).reduce((acc, [index, value]) => {
acc[+index] = value;
return acc;
}, []).map(([value]) => value);
console.log(JSON.stringify(arr)); // [null, 2, null, null, null, 6]

Create object from two array with custom key [closed]

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I have two array:
arrayA = ["Apple", "Banana", "Orange"]
arrayB = [1, 2, 3]
I need to make an object with these two array, but having custom keys.
Output desired:
{
{
id: 1,
name: "Apple"
},
{
id: 2,
name: "Banana"
},
{
id: 3,
name: "Orange"
}
}
what I have tried:
I have following some SO answer and it didnt meet my requirements:
result = {};
arrayA.forEach((item, i) => {
result["id"] = arrayB[i];
result["name"] = item;
});
the above code just reassign the value to the last item, hence I only got one object like this:
{
id: 3,
name: "Orange"
}

Just use map instead
const arrayA = ["Apple", "Banana", "Orange"];
const arrayB = [1, 2, 3];
const newArray = arrayA.map((item, i) => {
return {
"id" : arrayB[i],
"name" : item
}
});
console.log(newArray);

Dynamically assign object values to variable in JavaScript [closed]

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I need to assign the values of the below array of objects into defined variables which are initialized as empty strings.
What I have tried up until now:
const transaction = [{
number: 10,
value: "Ten"
},
{
number: 20,
value: "Twenty"
},
];
let transactionOneValue, transactionTwoValue, transactionOneNumber, transactionTwoNumber = "";
if (transaction.length > 0) {
transaction.forEach(item => {
[transactionOneNumber, transactionTwoNumber].forEach(num => num = item.number);
[transactionOneValue, transactionTwoValue].forEach(val => val = item.value);
});
}
Expected output:
transactionOneValue = "Ten",
transactionTwoValue = "Twenty",
transactionOneNumber = 10,
transactionTwoNumber = 20
How can I do it?

Destructuring seems to be simplest approach here, but I don't see how this would be useful. Creating separate variables for every item in a list isn't scalable.
let [
{number: transactionOneNumber, value: transactionOneValue},
{number: transactionTwoNumber, value: transactionTwoValue}
] = transaction

const transaction = [{
number: 10,
value: "Ten"
},
{
number: 20,
value: "Twenty"
},
];
let transactions = [];
if (transaction.length > 0) {
transaction.map((value, index, array) => {
for(x of Object.values(value)) {
transactions.push(x);
}
})
}
let transactionOneNumber = transactions[0],
transactionOneValue = transactions[1],
transactionTwoNumber = transactions[2],
transactionTwoValue = transactions[3];
console.log(transactionOneNumber);
console.log(transactionOneValue);
console.log(transactionTwoNumber);
console.log(transactionTwoValue);
output:
10
"Ten"
20
"Twenty"
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/values

re-create an Object to be 2D Array [closed]

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I have an object like this
{ '2020-08': {Invoice: 21400, Receipt: 20800, ...},
'2020-09': {Invoice: 8003.6, ...},
'2020-10': {Receipt: 7779.2, ...},
'2020-11': {Invoice: 32970, ...}
}
Wanna make it to be 2d array like this
[ ['2020-08', '2020-09', '2020-10', '2020-11'],
[ 21400 , 8003.6 , 0 , 32970 ], //Invoice
[ 20800 , 0 , 7779.2 , 0 ], //Receipt
...
]

It is very easy to achieve using Object.keys.
const data = {
'2020-08': {
Invoice: 21400,
Receipt: 20800
},
'2020-09': {
Invoice: 8003.6,
Receipt: 7779
},
'2020-10': {
Receipt: 7779.2,
Invoice: 32970
},
'2020-11': {
Invoice: 32970,
}
}
const res = []
const keys = [...Object.keys(data)]
const d = Object.keys(data).map(item => {
return data[item]["Invoice"] || 0
})
const d1 = Object.keys(data).map(item => {
return data[item]["Receipt"] || 0
})
console.log([keys, d, d1])

Try:
let result = [], key= [], invoice= [], receipt = [];
Object.keys(obj).forEach((x) => {
key.push(x);
invoice.push(obj[x].Invoice || 0);
receipt.push(obj[x].Receipt || 0);
});
result = [key,invoice,receipt];

How to merge two array and assign each iteration a key [closed]

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I have two array
arr1 = ["google.com", "none", "Twitter", "Facebook"]
arr2 = [6, 25, 1, 8]
Then my expected output would be like this
newArr = [
{
'medium': 'www.google.com',
'key': 6
},
{
'medium': 'none',
'key': 25
},
{
'medium': 'Twitter',
'key': 1
},
{
'medium': 'Facebook',
'key': 8
}
];
I have tried something like this but did not get the expected output
const result = arr1.reduce(function(result, field, index) {
result[arr2[index]] = field;
return result;
});
How can I achieve the output? Thanks.

You could do a map with index
const arr1 = ["google.com", "none", "Twitter", "Facebook"]
const arr2 = [6, 25, 1, 8]
const res = arr1.map((_, index) => ({
medium: arr1[index],
key: arr2[index],
}))
console.log(res)

This should work assuming arr1 and arr2 length always equal
function combineTwoArrays (arr1, arr2){
let result = []
for (let i = 0; i< arr1.length; i++){
result.push({
medium: arr1[i],
key: arr2[i]
})
}
return result
}