This question already has answers here:
Group objects by property in javascript
(8 answers)
Closed 2 years ago.
let attributeSet = [{
"id": 1,
"value": 11
},
{
"id" : 1,
"value": 12
},
{
"id" : 1,
"value" : 13
},
{
"id": "2",
"value" : "Qwerty"
}
]
I want to combine all the value in values like this
attributeSet = [
{
"id": 1,
"value": [11, 12, 13]
},
{
"id": 2,
"value": "Qwerty"
}
]
I am using two for loops for comparing the ids and then pushing it into an array. Can someone suggest me any better way.
You can use reduce & inside callback check if the accumulator object have the key same as id of the object under iteration. If not then create the key and push value to it
let attributeSet = [{
"id": 1,
"value": 11
},
{
"id": 1,
"value": 12
},
{
"id": 1,
"value": 13
},
{
"id": "2",
"value": "Qwerty"
}
]
let newData = attributeSet.reduce((acc, curr) => {
if (!acc[curr.id]) {
acc[curr.id] = {
id: curr.id,
value: []
}
}
acc[curr.id].value.push(curr.value)
return acc;
}, {});
console.log(Object.values(newData))
Related
I have an array of subscriptions group by the type (basic,medium ...)
`
[
[
"Basic",
[
{ "id": 2, "name": "Basic", "started_at": "2022-01-24", "count": 4 },
{ "id": 2, "name": "Basic", "started_at": "2022-03-16", "count": 2 },
{ "id": 2, "name": "Basic", "started_at": "2022-05-16", "count": 1 }
]
],
[
"Medium",
[
{ "id": 3, "name": "Medium", "started_at": "2022-02-21", "count": 1 },
{ "id": 3, "name": "Medium", "started_at": "2022-05-28", "count": 1 }
]
],
[
"Premium",
[{ "id": 4, "name": "Premium", "started_at": "2022-04-21", "count": 1 }]
],
[
"Master",
[
{ "id": 7, "name": "Master", "started_at": "2022-07-28", "count": 1 },
{ "id": 7, "name": "Master", "started_at": "2022-08-02", "count": 1 }
]
],
[
"Jedi",
[{ "id": 6, "name": "Jedi", "started_at": "2022-09-28", "count": 1 }]
]
]
`
What I want to do is return an array containing objects foreach sub with the following data(get the count value by month):
`
[
{
label: "Basic",
data: [4, 0, 2, 0, 1,0],
},
{
label: "Medium",
data: [0, 1, 0, 0, 1,0],
},
...
]
`
The data field should contain the count field foreach subscription corresponding to the month. For example for with count 4 in January and count 2 in March it will return [4,0,1] with 0 for February.
How can I achieve that ?
I did this but it's returning only the existing month values so there is no way to know which month that value is for.
subscriptions.map((item) => {
return {
label: item[0],
data: item[1].map((value, index) => {
return value.count;
}),
};
})
You could reduce the array and create a mapper object which maps each plan with month specifc count. Something like this:
{
"Basic": {
"1": 4,
"3": 2,
"5": 1
},
"Medium": {
"2": 1,
"5": 1
},
...
}
Then loop through the entries of the object and create objects with plan as label and an array of length: 12 and get the data for that specific month using the index
const input=[["Basic",[{id:2,name:"Basic",started_at:"2022-01-24",count:4},{id:2,name:"Basic",started_at:"2022-03-16",count:2},{id:2,name:"Basic",started_at:"2022-05-16",count:1}]],["Medium",[{id:3,name:"Medium",started_at:"2022-02-21",count:1},{id:3,name:"Medium",started_at:"2022-05-28",count:1}]],["Premium",[{id:4,name:"Premium",started_at:"2022-04-21",count:1}]],["Master",[{id:7,name:"Master",started_at:"2022-07-28",count:1},{id:7,name:"Master",started_at:"2022-08-02",count:1}]],["Jedi",[{id:6,name:"Jedi",started_at:"2022-09-28",count:1}]]];
const mapper = input.reduce((acc, [plan, subscriptions]) => {
acc[plan] ??= {}
for(const { started_at, count } of subscriptions)
acc[plan][+started_at.slice(5,7)] = count
return acc;
}, {})
const output =
Object.entries(mapper)
.map( ([label, subData]) => ({
label,
data: Array.from({ length: 12 }, (_, i) => subData[i+1] ?? 0)
}) )
console.log(output)
Note:
This assumes that the data is for a single year only. If it can be across years you'd have to create another level of nesting:
{
"Basic": {
"2022": {
"1": 3
}
}
}
started_at.slice(5,7) is used to get the month number. If the dates are not in the ISO 8601 format, you can use new Date(started_at).getMonth() + 1 to get the month part.
I have a problem with how to compare value to get largest number in more than one object.
For example i have 3 object (and this object can increment more than 3):
These each object saved in acc variable
[
{ "key": 1, "value": 1 },
{ "key": 1, "value": 3 },
{ "key": 1, "value": 6 },
]
[
{ "key": 2, "value": 2 },
{ "key": 2, "value": 5 },
{ "key": 2, "value": 9 },
]
[
{ "key": 3, "value": 1 },
{ "key": 3, "value": 2 },
{ "key": 3, "value": 3 },
]
First i get the last value from each object with console.log(acc[acc.length - 1].value);
and it will print:
6
9
2
Then i don't know how to compare the numbers? And get result:
{ "key": 2, "value": 9 }
I have try console.log(Math.max(acc[acc.length - 1].value));, but its not working because that number is not inside one array.
This is screenshot if i log console.log(acc)
First merge all the nested objects by .flat() and perform .reduce() operation on them. in every iteration look b.value is greater than the object value of accumulator a.value, if it's the case we need to update the object of the accumulator a.
const arr = [[ { "key": 1, "value": 1 }, { "key": 1, "value": 3 }, { "key": 1, "value": 6 }, ], [ { "key": 2, "value": 2 }, { "key": 2, "value": 5 }, { "key": 2, "value": 9 }, ], [ { "key": 3, "value": 1 }, { "key": 3, "value": 2 }, { "key": 3, "value": 3 }, ]];
console.log(arr.flat().reduce((a,b)=>(b.value > a.value ? b : a)));
New requirement:
const arr = [[
{ "key": 1, "value": 1 },
{ "key": 1, "value": 3 },
{ "key": 1, "value": 6 },
{ "key": 3, "value": 6 },
],
[
{ "key": 2, "value": 2 },
{ "key": 2, "value": 5 },
{ "key": 2, "value": 9 },
],
[
{ "key": 3, "value": 1 },
{ "key": 3, "value": 2 },
{ "key": 3, "value": 3 },
]];
let results = [{key: -1, value: -1}]; //initial value I assume data don't have a value less than -1
arr.forEach((item) => { //Simulating your current situation
item.forEach(it => { //here we get an array in each iteration
if (it.value > results[0].value) {
results = [it];
}
else if (it.value === results[0].value) {
results.push(it);
}
});
});
console.log(results);
This question already has answers here:
From an array of objects, extract value of a property as array
(24 answers)
Closed 1 year ago.
I have an object:
[
{
"id": 10,
"name": "comedy"
},
{
"id": 12,
"name": "documentary"
},
{
"id": 11,
"name": "scifi"
}
]
I need to take only the id values and add them into 1 array like so:
[ 10, 12, 13 ]
or
{ 10, 12, 13 }
I am trying:
const getIDs = value.map( ( { id } ) => ( {
id: id
} ) );
But it creates:
[
{
"id": 10
},
{
"id": 12
},
{
"id": 11
}
]
Inside the map just return the id values instead of objects
Here is the quick solution
const values = [
{
"id": 10,
"name": "comedy"
},
{
"id": 12,
"name": "documentary"
},
{
"id": 11,
"name": "scifi"
}
]
const getIDs = values.map(({id}) => id);
console.log(getIDs)
This question already has answers here:
How to sort an array based on the length of each element?
(12 answers)
Closed 1 year ago.
I have an array like below, and I need to sort the array by the string length of name field.
for an example,
[
{
"_id": 10,
"name": "AAAAAA"
},
{
"_id": 11,
"name": "AA"
},
{
"_id": 12,
"name": "AAAA"
},
{
"_id": 13,
"name": "A"
},
{
"_id": 14,
"name": "AAAAAAAA"
}
]
I need the array like this,
[
{
"_id": 13,
"name": "A"
},
{
"_id": 11,
"name": "AA"
},
{
"_id": 12,
"name": "AAAA"
},
{
"_id": 10,
"name": "AAAAAA"
},
{
"_id": 14,
"name": "AAAAAAAA"
}
]
can any one help me out with this. Thanks.
This can be accomplished with the _.orderBy method:
_.orderBy(data, [({ name }) => name.length, 'name'], ['desc']);
Here is a break-down:
I threw some "B"s into the mix to show the secondary sorting (after length is compared). Sorting the length alone is not unique enough.
const data = [
{ "_id": 1, "name": "AAAAAA" },
{ "_id": 2, "name": "AA" },
{ "_id": 3, "name": "AAAA" },
{ "_id": 4, "name": "A" },
{ "_id": 5, "name": "AAAAAAAA" },
{ "_id": 6, "name": "BBBBBB" },
{ "_id": 7, "name": "BB" },
{ "_id": 8, "name": "BBBB" },
{ "_id": 9, "name": "B" },
{ "_id": 10, "name": "BBBBBBBB" }
];
const sorted = _.orderBy(
data, // Data to be sorted
[
({ name: { length } }) => length, // First, sort by length
'name' // Them sort lexicographically
], [
'desc', // Length (descending)
'asc' // This is implied, and could be removed
]
);
console.log(sorted);
.as-console-wrapper { top: 0; max-height: 100% !important; }
<script src="https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.21/lodash.min.js"></script>
This question already has answers here:
How to get names of enum entries?
(43 answers)
Closed 4 years ago.
I have an enum file where I have defined an object for PaymentTypes:
export enum PaymentTypes {
Invoice = 1,
CreditCard = 2,
PrePayment = 3,
}
Now, when I receive data as an array from my database I also receive the PaymentType as a number:
order:
[
{ "id": 0, "name": "Available", "PaymentType": 1 },
{ "id": 1, "name": "Ready", "PaymentType": 3 },
{ "id": 2, "name": "Started", "PaymentType": 2 }
];
Now my question is, how can I filter out each payment type in the array and convert the number to the string that's defined in the enum file so that I can us this data to display it to the user in the front end?
So that I have something like this that I can work with:
orderFiltered:
[
{ "id": 0, "name": "Available", "PaymentType": "Invoice" },
{ "id": 1, "name": "Ready", "PaymentType": "PrePayment" },
{ "id": 2, "name": "Started", "PaymentType": "CreditCard" }
];
You can use map to create a new array of objects that contains the original data and the name of the enum member, which you can get using PaymentTypes[PaymentType]
let order = [
{ "id": 0, "name": "Available", "PaymentType": 1 },
{ "id": 1, "name": "Ready", "PaymentType": 3 },
{ "id": 2, "name": "Started", "PaymentType": 2 }
];
enum PaymentTypes {
Invoice = 1,
CreditCard = 2,
PrePayment = 3,
}
let orderFiltered = order.map(o => Object.assign({}, o, { PaymentTypeDisplayName: PaymentTypes[o.PaymentType] }));
console.log(orderFiltered);
One thing to note though is that using the enum member name as a display might not be the friendliest of use experiences.