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Is there way to rearange objects in array that the value becomes the key?

I'm stuck on this type of situation where the values of the object is changed to a different value. Is there way to shift a value to a key or would simply deleting and adding be better? I tried to loop to see which of the keys overlap in value and using the if statement and conditions i tried adding or deleting using Array methods. However, since the inter data is an object i am sruggling to find the right methods or even the process. I also tried using a function to insert the data and pushing to a new empty array that is returned from the function.
If I have objects in an array like so:
const data = [
{
"date": "12/22",
"treatment": "nausea",
"count": 2
},
{
"date": "12/23",
"treatment": "cold",
"count": 3
},
{
"date": "12/22",
"treatment": "cold",
"count": 2
}
];
and wanting to change the data like so:
const newData = [
{
"date": "12/22",
"cold": 2
"nausea": 2,
},
{
"date": "12/23",
"cold": 3
}
];

try this code using loop and reduce and every time add to new array
const data = [
{
"date": "12/22",
"treatment": "nausea",
"count": 2
},
{
"date": "12/23",
"treatment": "cold",
"count": 3
},
{
"date": "12/22",
"treatment": "cold",
"count": 2
}
];
const newData = [];
const dataByDate = data.reduce((acc, curr) => {
if (!acc[curr.date]) {
acc[curr.date] = { date: curr.date };
}
acc[curr.date][curr.treatment] = curr.count;
return acc;
}, {});
for (let date in dataByDate) {
newData.push(dataByDate[date]);
}
console.log(newData);

We want to reduce the data by unique dates. This can be done with:
An object as a dictionary,
Set or Map, or
Some other custom implementation.
Prefer to use Array.reduce() when reducing an array. This is standardized and more expressive than a custom implementation.
Using a map-like structure as the accumulator allows reduction of the dates by uniqueness and the data itself, simultaneously.
Note: Properties of objects are converted to Strings (except for Symbols). So if you want to use different "keys" that are equal after conversion (e.g. 0 and "0"), you cannot use objects; use Map instead.
(All our dates are Strings already, so this warning does not apply here.)
When using an object we can use the nullish coalescing assignment ??=: This allows us to assign an initial "empty" entry ({ date: dataEntry.date }) when encountering a new unique date.
Further, that assignment evaluates to the dictionary's entry; the entry that was either already present or just assigned.
Then we only need to assign the treatment and its count as a key-value pair to the entry.
const data = [
{ "date": "12/22", "treatment": "nausea", "count": 2 },
{ "date": "12/23", "treatment": "cold", "count": 3 },
{ "date": "12/22", "treatment": "cold", "count": 2 }
];
const newData = reduceByDate(data);
console.log(newData);
function reduceByDate(data) {
const dataByDate = data.reduce((dict, dataEntry) => {
const dictEntry = dict[dataEntry.date] // Get existing or ...
??= { date: dataEntry.date }; // ... just initialized entry.
dictEntry[dataEntry.treatment] = dataEntry.count;
return dict;
}, {});
// Transform dictionary to array of reduced entries
return Object.values(dataByDate);
}

You can make use of reduce() and Object.assign().
First we use reduce to combine objects with the same date into one object and then use assign to merge the values:
const data = [{
"date": "12/22",
"treatment": "nausea",
"count": 2
},
{
"date": "12/23",
"treatment": "cold",
"count": 3
},
{
"date": "12/22",
"treatment": "cold",
"count": 2
}
];
const newData = data.reduce((acc, curr) => {
const dateIndex = acc.findIndex(item => item.date === curr.date);
if (dateIndex === -1) {
acc.push({
date: curr.date,
[curr.treatment]: curr.count
});
} else {
acc[dateIndex] = Object.assign({}, acc[dateIndex], {
[curr.treatment]: curr.count
});
}
return acc;
}, []);
console.log(newData)

How to get this output from JSON in javascipt ny comparing student_id from mark_details and students_detail?

JSON Object:
{
"students_detail": [
{
"student_id": 1,
"name": "abc",
"roll_number": 10
},
{
"student_id": 2,
"name": "pqr",
"roll_number": 12
}
],
"subject_details": [
{
"subject_id": 1,
"subject_name": "math"
},
{
"subject_id": 2,
"subject_name": "english"
}
],
"exam_details": [
{
"exam_id": 1,
"exam_name": "Prelim"
}
],
"mark_details": [
{
"id": 1,
"exam_id": 1,
"subject_id": 1,
"student_id": 1,
"mark": 51
},
{
"id": 2,
"exam_id": 1,
"subject_id": 2,
"student_id": 2,
"mark": 61
}
]
}
Ouptut:
{
"student_mark_details": [
{
"abc": {
"roll_number": 10,
"Prelim": [
{
"subject_name": "math",
"mark": 51
}
]
},
"pqr": {
"roll_number": 12,
"Prelim": [
{
"subject_name": "english",
"mark": 61
}
]
}
}
]
}
i tried using loops and accesing student_id in both object and comparing them but code gets too messy and complex,is there any way i can use map() or filter() in this or any other method.
i have no idea where to start,my brain is fried i know im asking lot but help will be appreciated (any link/source where i can learn this is fine too)

Your output object really has a weird format: student_mark_details is an array of size 1 that contains an object that has all your students in it. Anyway, this should give you what you need. It is a format that you find often because it is a system with primary key and secondary key used a lot in databases.
The key to manage that is to start with what is at the core of what you are looking for (here, you want to describe students, so you should start from there), and then navigate the informations you need by using the primary/secondary keys. In JS, you can use the find() function in the case where one secondary key can be linked only to one primary key (ex: one mark is linked to one exam), and the filter() function when a secondary key can be linked to multiple secondary keys (ex: a student is linked to many grades).
I am not sure if this is 100% what you need because there are maybe some rules that are not shown in your example, but it solves the problem you submitted here. You might have to test it and change it depending of those rules. I don't know what your level is so I commented a lot
const data = {
"students_detail": [
{
"student_id": 1,
"name": "abc",
"roll_number": 10
},
{
"student_id": 2,
"name": "pqr",
"roll_number": 12
}
],
"subject_details": [
{
"subject_id": 1,
"subject_name": "math"
},
{
"subject_id": 2,
"subject_name": "english"
}
],
"exam_details": [
{
"exam_id": 1,
"exam_name": "Prelim"
}
],
"mark_details": [
{
"id": 1,
"exam_id": 1,
"subject_id": 1,
"student_id": 1,
"mark": 51
},
{
"id": 2,
"exam_id": 1,
"subject_id": 2,
"student_id": 2,
"mark": 61
}
]
}
function format(data) {
const output = {
"student_mark_details": [{}]
};
//I start by looping over the students_detail because in the output we want a sumary by student
data.students_detail.forEach(student => {
//Initialization of an object for a particular student
const individualStudentOutput = {}
const studentId = student.student_id;
const studentName = student.name;
//The rollNumber is easy to get
individualStudentOutput.roll_number = student.roll_number;
//We then want to find the exams that are linked to our student. We do not have that link directly, but we know that our student is linked to some marks
//Finds all the marks that correspond to the student
const studentMarkDetails = data.mark_details.filter(mark => mark.id === studentId);
studentMarkDetails.forEach(individualMark => {
//Finds the exam that corresponds to our mark
const examDetail = data.exam_details.find(exam => individualMark.exam_id === exam.exam_id);
//Finds the subject that corresponds to our mark
const subjectDetail = data.subject_details.find(subject => individualMark.subject_id === subject.subject_id);
//We then create a grade that we will add to our exam
const grade = {
subject_name: subjectDetail.subject_name,
mark: individualMark.mark
}
//We then want to add our grade to our exam, but we don't know if our output has already have an array to represent our exam
//So in the case where it does not exist, we create one
if (!individualStudentOutput[examDetail.exam_name]) {
individualStudentOutput[examDetail.exam_name] = [];
}
//We then add our grade to the exam
individualStudentOutput[examDetail.exam_name].push(grade);
});
//Now that we have finished our individual output for a student, we add it to our object
output.student_mark_details[0][studentName] = individualStudentOutput;
})
return output;
}
console.log(JSON.stringify(format(data)))

Sort max date from Object

Trying to sort the object with the max date. One id may have multiples dates. Below is the format of the object where id:123 has two dates. So I am trying to take the max date for the user 123. I used the sort method and storing the array[0] but still there is something missing.
var arr = [
{
"scores": [
{
"score": 10,
"date": "2021-06-05T00:00:00"
}
],
"id": "3212"
},
{
"scores": [
{
"score": 10,
"date": "2021-06-05T00:00:00"
},
{
"score": 20,
"date": "2021-05-05T00:00:00"
}
],
"id": "123"
},
{
"scores": [
{
"score": 5,
"date": "2021-05-05T00:00:00"
}
],
"id": "321"
}
]
What I tried is
_.each(arr, function (users) {
users.scores = users.scores.filter(scores => new Date(Math.max.apply(null, scores.date)));
return users;
});
Expecting the output to look like the following with the max date selected.
[
{
"scores": [
{
"score": 10,
"date": "2021-06-05T00:00:00"
}
],
"id": "3212"
},
{
"scores": [
{
"score": 10,
"date": "2021-06-05T00:00:00"
}
],
"id": "123"
},
{
"scores": [
{
"score": 5,
"date": "2021-05-05T00:00:00"
}
],
"id": "321"
}
]

Your filter callback function is not performing a comparison to filter the correct element. Also, although applying the "maximum" algorithm on the dates as string would be fine in your case (because of the date format you have), it would be much safer to transform the date strings into date objects to consistantly get correct results regardless of the format.
In the solution below, you can use a combination of Array.map() and Array.sort() to copy and process your data in the correct result.
const data = [{
'scores': [{
'score': 10,
'date': '2021-06-05T00:00:00'
}],
'id': '3212'
}, {
'scores': [{
'score': 10,
'date': '2021-06-05T00:00:00'
}, {
'score': 20,
'date': '2021-05-05T00:00:00'
}],
'id': '123'
}, {
'scores': [{
'score': 5,
'date': '2021-05-05T00:00:00'
}],
'id': '321'
}];
// map the data and return the updated objects as the result
const result = data.map((user) => {
// copy the scores array to not mutate the original data
const sortedScores = user.scores.slice();
// sort the scores array by date descending
sortedScores.sort((a, b) => (new Date(b.date) - new Date(a.date)));
// return the same user with the first score from the sorted array
return {
...user,
scores: [sortedScores[0]]
};
});
console.log(result);

Elasticsearch - find closest number when scoring results

I need a way to match the closest number of an elasticsearch document.
I'm wanting to use elastic search to filter quantifiable attributes and have been able to achieve hard limits using range queries accept that results that are outside of that result set are skipped. I would prefer to have the closest results to multiple filters match.
const query = {
query: {
bool: {
should: [
{
range: {
gte: 5,
lte: 15
}
},
{
range: {
gte: 1979,
lte: 1989
}
}
]
}
}
}
const results = await client.search({
index: 'test',
body: query
})
Say I had some documents that had year and sales. In the snippet is a little example of how it would be done in javascript. It runs through the entire list and calculates a score, then based on that score it sorts them, at no point are results filtered out, they are just organized by relevance.
const data = [
{ "item": "one", "year": 1980, "sales": 20 },
{ "item": "two", "year": 1982, "sales": 12 },
{ "item": "three", "year": 1986, "sales": 6 },
{ "item": "four", "year": 1989, "sales": 4 },
{ "item": "five", "year": 1991, "sales": 6 }
]
const add = (a, b) => a + b
const findClosestMatch = (filters, data) => {
const scored = data.map(item => ({
...item,
// add the score to a copy of the data
_score: calculateDifferenceScore(filters, item)
}))
// mutate the scored array by sorting it
scored.sort((a, b) => a._score.total - b._score.total)
return scored
}
const calculateDifferenceScore = (filters, item) => {
const result = Object.keys(filters).reduce((acc, x) => ({
...acc,
// calculate the absolute difference between the filter and data point
[x]: Math.abs(filters[x] - item[x])
}), {})
// sum the total diffences
result.total = Object.values(result).reduce(add)
return result
}
console.log(
findClosestMatch({ sales: 10, year: 1984 }, data)
)
<script src="https://codepen.io/synthet1c/pen/KyQQmL.js"></script>
I'm trying to achieve the same thing in elasticsearch but having no luck when using a function_score query. eg
const query = {
query: {
function_score: {
functions: [
{
linear: {
"year": {
origin: 1984,
},
"sales": {
origin: 10,
}
}
}
]
}
}
}
const results = await client.search({
index: 'test',
body: query
})
There is no text to search, I'm using it for filtering by numbers only, am I doing something wrong or is this not what elastic search is made for and are there any better alternatives?
Using the above every document still has a default score, and I have not been able to get any filter to apply any modifiers to the score.
Thanks for any help, I new to elasticsearch links to articles or areas of the documentation are appreciated!

You had the right idea, you're just missing a few fields in your query to make it work.
It should look like this:
{
"query": {
function_score: {
functions: [
{
linear: {
"year": {
origin: 1984,
scale: 1,
decay: 0.999
},
"sales": {
origin: 10,
scale: 1,
decay: 0.999
}
}
},
]
}
}
}
The scale field is mandatory as it tells elastic how to decay the score, without it the query just fails.
The decay field is not mandatory, however without it elastic does not really know how to calculate the new score to documents so it will end up giving a default score only to documents in the range of origin + scale which is not useful for us.
source docs.
I also recommend you limit the result size to 1 if you want the top scoring document, otherwise you'll have add a sort phase (either in elastic or in code).
EDIT: (AVOID NULLS)
You can add a filter above the functions like so:
{
"query": {
"function_score": {
"query": {
"bool": {
"must": [
{
"bool": {
"filter": [
{
"bool": {
"must": [
{
"exists": {
"field": "year"
}
},
{
"exists": {
"field": "sales"
}
},
]
}
}
]
}
},
{
"match_all": {}
}
]
}
},
"functions": [
{
"linear": {
"year": {
"origin": 1999,
"scale": 1,
"decay": 0.999
},
"sales": {
"origin": 50,
"scale": 1,
"decay": 0.999
}
}
}
]
}
}
}
Notice i have a little hack going on using match_all query, this is due to filter query setting the score to 0 so by using the match all query i reset it back to 1 for all matched documents.
This can also be achieved in a more "proper" way by altering the functions, a path i choose not to take.

How to generate an array of unique objects from api?

I'm trying to disable booked times from calendar, depending on the date. My goal is to create an array, which holds objects with single date and array of booked times.
I have created an api, which outputs something like this:
"bookings": [
{
"_id": "5ce1b8792598adasf452",
"workType": "Nail polishing",
"client": "Mary Johnson",
"date": "2019-05-31T00:00:00.000Z",
"bookingTime": "09:00"
},
{
"_id": "5ce1b8753hs53gasf452",
"workType": "Makeup",
"client": "Kate Bush",
"date": "2019-05-31T00:00:00.000Z",
"bookingTime": "10:00"
}
]
I've tried using Sets, filters, but I just can't seem to wrap my head around how to implement it to my own code.
Snippet of my code:
bookedTimes: []
fetchBookedTimes() {
axios.get("http://localhost:8080/api/bookings").then(res => {
for (var i = 0; i < res.data.bookings.length; i++) {
this.bookedTimes.push({
date: moment(res.data.bookings[i].date).format("YYYY-MM-DD"),
times: [res.data.bookings[i].bookingTime.substring(0,2)]
});
}
});
}
I expect the output to be
bookedTimes: [
{
date: "2019-05-31",
times: ["09", "10"]
},
{
date: "2019-06-01",
times: ["10", "11"]
}
]
But the actual output is
bookedTimes: [
{
date: "2019-05-31",
times: ["09"]
},
{
date: "2019-05-31",
times: ["10"]
},
{
date: "2019-06-01",
times: ["10"]
},
{
date: "2019-06-01",
times: ["11"]
}
]

As per the code, the actual output is correct. You are looping the response and pushing the data to an array. If you want to group them by date, then you have to create an object and then convert it to the expected output.
var result = res.data.bookings.reduce(function (defaultValue, booking) {
var date = moment(booking.date).format("YYYY-MM-DD");
defaultValue[date] = defaultValue[date] || {date: date, times: []};
defaultValue[date].times.push(booking.bookingTime.substring(0,2));
return defaultValue;
}, {});
console.log(Object.values(result));

You can simply use reduce()
const arr = [
{
"_id": "5ce1b8792598adasf452",
"workType": "Nail polishing",
"client": "Mary Johnson",
"date": "2019-05-31T00:00:00.000Z",
"bookingTime": "09:00"
},
{
"_id": "5ce1b8753hs53gasf452",
"workType": "Makeup",
"client": "Kate Bush",
"date": "2019-05-31T00:00:00.000Z",
"bookingTime": "10:00"
},
{
"_id": "5ce1b8753hs53gasf452",
"workType": "Makeup",
"client": "Kate Bush",
"date": "2019-06-31T00:00:00.000Z",
"bookingTime": "11:00"
},
{
"_id": "5ce1b8753hs53gasf452",
"workType": "Makeup",
"client": "Kate Bush",
"date": "2019-06-31T00:00:00.000Z",
"bookingTime": "12:00"
}
]
const res = arr.reduce((ac,{date,bookingTime}) => {
ac[date] = ac[date] || {date,bookingTime:[]}
ac[date].bookingTime.push(bookingTime.slice(0,2));
return ac;
},{})
console.log(Object.values(res))

You're pushing values directly into array but you need to group them by date so you can use an object and then push values to array in the end
Here temp is used to group values by date
We check for date it exists we push the time value to times array if not we create a new property on temp
In the end we push values to this.bookedTimes array
fetchBookedTimes() {
axios.get("http://localhost:8080/api/bookings").then(res => {
let temp = {}
for (var i = 0; i < res.data.bookings.length; i++) {
let date = moment(res.data.bookings[i].date).format("YYYY-MM-DD"),
let time = [res.data.bookings[i].bookingTime.substring(0,2)]
temp[date] = temp[date] || {date: date, times:[]}
temp[date].times.push(time)
});
}
this.bookedTimes.push(Object.values(temp))
});
}

First, check if the date of already in the array. Check if 'times' already exist in 'object.times', if not, push it to the 'object.times' array.
Please see the code below.
const date = moment(res.data.bookings[i].date).format("YYYY-MM-DD");
const times = res.data.bookings[i].bookingTime.substring(0, 2);
const arrayIndex = bookedTimes.findIndex(item => item.date === date);
//Check if date already exist in array
if (arrayIndex !== -1) {
//Check if 'times' already exist in 'object.times'
if (!bookedTimes[arrayIndex].times.includes(times)) {
//Push 'times' in 'object.times'
bookedTimes[arrayIndex].times.push(times);
}
} else {
//Push a new object into the array
bookedTimes.push({
date: date,
times: [times]
});
}