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FInd duplicates withtin array based on certain keys using lodash?

I have an array like this
let data = [{x:1,y:2,z:3},{x:1,y:2,z:3},{x:1,y:2,z:4},{x:11,y:2,z:3}]
Now I want to get only those items whose x,y,z values are the same.so expected output should be
{x:1,y:2,z:3}
Because {x:1,y:2,z:3} has duplicate values but rest of them not so I don't want to get rest of them because they do not have any duplicates. Please tell me how can I achieve this?

For lodash 4.17.15,
You can first use _.uniqWith and _.isEqual to find the unique values.
_.uniqWith(data, _.isEqual); // [{x:1,y:2,z:3},{x:1,y:2,z:4},{x:11,y:2,z:3}]
Then use _.difference to remove the unique values from the array, leaving just the duplicates
_.difference(data, _.uniqWith(data, _.isEqual)); // [{x:1,y:2,z:3}]

let data = [{x:1,y:2,z:3},{x:1,y:2,z:3},{x:1,y:2,z:4},{x:11,y:2,z:3},{x:11,y:2,z:3}]
function filterDuplicates(data) {
let dic = {};
data.forEach(obj => {
let strObj = JSON.stringify(obj, Object.keys(obj).sort());
if(strObj in dic) {
++dic[strObj];
return;
}
dic[strObj] = 0;
})
return Object.entries(dic).filter(([key, value]) => value > 0).map(([el]) => JSON.parse(el));
}
console.log(filterDuplicates(data));

Build an object to track the duplicates and use Object.values and filter
let data = [
{ x: 1, y: 2, z: 3 },
{ x: 1, y: 2, z: 3 },
{ x: 1, y: 2, z: 4 },
{ x: 11, y: 2, z: 3 },
];
const all = {};
data.forEach(({ x, y, z }) => {
const key = `x${x}y${y}z${z}`;
all[key] = key in all ? { x, y, z } : null;
});
const res = Object.values(all).filter(Boolean);
console.log(res);

Add Key To Javascript Array

I'm looking to append keys to the array which I have created, so I have an array of numbers:
var Array1 = [1, 2, 3, 4, 5];
I want to convert the array so it looks like this:
Array1 = [{ x: 1 }, { x: 2 }, { x: 3 }, { x: 4 }, { x: 5 }];
How do I append to each value in the array like so?
https://www.sitepoint.com/a-beginners-guide-to-data-binding-in-d3-js/ - Within this article, we can see they have an array called 'Data' - An array of objects. Now I have a simple array full of numbers and I need it to be converted as described above

You could use Array#map together with short hand properties for a new object for each element of the array.
var array = [1, 2, 3, 4, 5],
objects = array.map(x => ({ x }));
console.log(objects);
.as-console-wrapper { max-height: 100% !important; top: 0; }

Array1 = Array1.map(entry => ({x: entry}));

Compare 2 array using lodash

I have 2 arrays of similar element but arranged in different order.
I have a source variable with is arranged according to arr1 based on key src and file of arr1 and source.
Now i want to arranged destination variable according to arr2.
Could you please let me know how we can done with lodash?
arr1 = [{x:0,y:1,src:a1},{x:1,y:1,src:b1},{x:2,y:1,src:c1}]
arr2 = [{x:1,y:1,src:b1},{x:1,y:1,src:a1},{x:1,y:1,src:c1}]
source = [{file:a1},{file:b1},{file:c1}]
Destination = [{file:b1},{file:a1},{file:c1}]

You could use lodash's map routine to achieve this:
let source = [{
x: 1,
y: 1,
src: 'b1'
}, {
x: 1,
y: 1,
src: 'a1'
}, {
x: 1,
y: 1,
src: 'c1'
}]
let destination = _.map(source, value => {
return { file: value['src']}
})
See here for an example.
Also note that you can achieve this using the standard JavaScript map function.

Create one array from 2 Arrays with keys x & y

I have 2 Arrays xDates and yMentions
xDates
[1453766400000, 1453852800000, 1453939200000...
yMentions
[5160, 5240, 7090...
Goal is an Array like so:
[
{
x: 1453766400000,
y: 5160
},
...
]
Trying to use Ramda Zip thought zipObj would be what I need, but the following produces just 1 object:
R.zipObj(['x', 'x', 'x'], [1, 2, 3]); => {"x": 3}
Figured perhaps I run R.zipObj on the x then the y arrays, then zip them together then set that as the Array for mentionsPointsArray below:
const createMentionPoints = (frequencyPoints, termsData) => {
const yMentions = termsData.mentions;
const propX = R.prop('x');
const xPointsFromFrequency = R.map(propX, frequencyPoints);
console.log('xDates', xPointsFromFrequency)
console.log('yMentions', yMentions)
const mentionsPointsArray = []
return frequencyPoints;
};

You should use Array#map function.
The map() method creates a new array with the results of calling a provided function on every element in this array.The provided function is a callback.
The elements from the result array are objects, like this: {"x":item, "y":yMentions[i]}.
var xDates=[1453766400000, 1453852800000, 1453939200000];
var yMentions=[5160, 5240, 7090];
console.log(xDates.map(function(elem,i){
return {"x":elem,"y":yMentions[i]}
}));

The ramda solution http://ramdajs.com/docs/#zipWith
var createPoints = (x, y) => {
return { x: x, y: y }
};
R.zipWith(createPoints, [1, 2, 3], ['a', 'b', 'c']);
// returns: [{"x": 1, "y": "a"}, {"x": 2, "y": "b"}, {"x": 3, "y": "c"}]

I think the cleanest point-free version would be:
const data1 = ['a', 'b', 'c']
const data2 = [1, 2, 3]
R.zipWith(R.objOf, data1, data2)
Please have a look at a working REPL here

Convert Js Array to JSON object with keys

I want to use the same object for jQplot and a library built on jQtable.
jQplot is fine with arrays but jQtable's library needs an named object (dictionary).
vals =
[
[1, 2],
[3,5.12],
[5,13.1],
[7,33.6],
[9,85.9],
[12,54],
[11,219.9]
];
This is my js array
I want it to be like
{
data: [{
X: 1,
Y: 2
},
{
X: 3,
Y: 5.12
},
{
X: 5,
Y: 13.1
}]
}
How to convert js array into named JSON array of objects? Are there any built in methods or I define my own method to read up that array and create a String for JSON?

var array = vals.map(function(val) {
return {
X : val[0],
Y : val[1]
};
});

var data = Object.keys(vals).map(function(key) {
return {X : vals[key][0], Y : vals[key][1]};
});