I am trying find unique ObjectIds from monogdb ObjectId array using filter. For some reason I am not getting unique array back. Is there is some other way to get unique array back ?
var objIds = [ 5ad3509fbb426a4f4a382754,
5ad3509fbb426a4f4a382752,
5ad3509fbb426a4f4a382754,
5ad3509fbb426a4f4a382751
]
Here is the filter code
objIds = objIds.filter((x, i, a) => a.indexOf(x) == i)
I am expecting following array after filter
[ 5ad3509fbb426a4f4a382754,
5ad3509fbb426a4f4a382752,
5ad3509fbb426a4f4a382751
]
If you are passing in an array and the elements inside the array is a string then this should work.
function getUniqueValues(arr) {
return arr.filter((e, i) => arr.indexOf(e) === i)
}
you can use lodash's uniq method to do this easily.
const { uniq } = require("lodash");
var objIds = [
"5ad3509fbb426a4f4a382754",
"5ad3509fbb426a4f4a382752",
"5ad3509fbb426a4f4a382754",
"5ad3509fbb426a4f4a382751"
];
console.log(uniq(objIds));
will give the following output
[ '5ad3509fbb426a4f4a382754',
'5ad3509fbb426a4f4a382752',
'5ad3509fbb426a4f4a382751' ]
Related
I was updating may images array which is found in following format:
[
"d756d3d2b9dac72449a6a6926534558a.jpg",
"b607aa5b2fd58dd860bfb55619389982.jpg",
"f937c8fddbe66ab03c563f16d5cfa50c.jpg"
]
So to delete a single image d756d3d2b9dac72449a6a6926534558a.jpg from this array column I used the filter method like below:
$collection = collect($imageColumn)->filter(
function ($valueTobeDeleted) use ($array) {
return !in_array($valueTobeDeleted, $array);
}
);
so after filter I wan to update my database with the new collection, but the new collection is in a map format like below
array:2 [
1 => "b607aa5b2fd58dd860bfb55619389982.jpg"
2 => "f937c8fddbe66ab03c563f16d5cfa50c.jpg"
]
the problem is i don't need those keys 1, and 2 my expectation was
array:2 [
"b607aa5b2fd58dd860bfb55619389982.jpg"
"f937c8fddbe66ab03c563f16d5cfa50c.jpg"
]
How can I achieve my expectation? How can I convert them to array?
Because you are using a Collection, you can do ->values() at the end so you convert all keys into integer keys and beginning from 0, like a normal non-associative array:
$collection = collect($imageColumn)->filter(
function ($valueTobeDeleted) use ($array) {
return !in_array($valueTobeDeleted, $array);
}
)
->values();
In order to re-index an array, you can use the array_values PHP function:
$arr = array_values($arr);
This will fix the keys.
Use array_values to get a an array of that associatve array.
$collection = collect($imageColumn)->
$filtered = filter(function ($valueTobeDeleted) use ($array) {
return !in_array($valueTobeDeleted, $array);
});
$filtered = array_values($filtered);
Newbie here and this is a project I'm building to learn. I'm going around in circles so forgive my ignorance please. I'm now not even sure that what I want to do is possible. I also understand that there are probably better ways to achieve my ultimate goal but this is what I have.
I have an array that includes some user input.
"participants": [ {
"name": "Cristina",
"email": "cristina#gmail",
"yourPerson": "Richard",
"spouseEmail": "Richard#gmail" } ] }
I want to pull the "name" and "youPerson" values and use them as a key:value pair. So name would be the key and yourPerson would be the value.
I thought I could use a forEach but no matter what I do I either get an undefined array or I copy the entire array, not just those two fields.
here is my code at the moment:
participantArray = [];
namePlusSpouseArray = [];
submitParticipant() {
this.participantArray.push(this.participantForm.value);
console.log(this.participantArray)
this.createNamePlusSpouseArray();
}
createNamePlusSpouseArray() {
this.participantArray.forEach(name => {
this.namePlusSpouseArray.push(this.participantArray[name]);
console.log(this.namePlusSpouseArray)
});
}
Not sure if you want a result array of key value pairs, or you want 1 object/map/dictionary/lookup of name -> youPerson
Assuming you want an array containing key value pairs, you can use map
this.namePlusSpouseArray = this.participantArray.map(participant => ({
[participant.name]: participant.youPerson
});
If you want a lookup of name -> youPerson, the "namePlusSpouseArray" shouldn´t be an array but instead just an object
namePlusSpouseLookup = {};
this.participantArray.forEach(participant => {
this.namePlusSpouseLookup[participant.name] = participant.youPerson;
});
The simplest solution is:
const participantArray = {
"participants": [ { "name": "Cristina", "email": "cristina#gmail", "yourPerson": "Richard", "spouseEmail": "Richard#gmail" } ] };
const createPair = participants => {
return participants.map(participant =>
({ [participant.name]: participant.yourPerson}))
}
console.log(createPair(participantArray.participants));
So I'm working with states in React, and i want to compare the two arrays/state and get the data from the first array that doesn't match with the data on the second array.
The first array is a state, and the second one is an array.
My first state/array looks like this = state : [ { id : id , productNumber : "productnumber"}... ] and the second array loos like this = array ["productnumber","productnumber"...],
and here what is my code's look like.
let newArray = [];
state.forEach(product=>{
array.forEach(productNumber=>{
if(product.productNumber !== productNumber){
newArray = [...newArray,product.productNumber];
}
})
})
and it doesn't work, it stores all the data from the first array/state and even doubled it. I tried using nested if statements, still doesn't. I don't know what todo.
let newArray = [];
state.forEach(({productNumber}) => {
if (array.indexOf(productNumber) === -1) {
newArray = [...newArray, productNumber];
}
})
Or similarly, you can filter the state array and return the products with productNumber not in your second array.
const newArray = state.filter(({productNumber}) => array.indexOf(productNumber) === -1);
I have two arrays one with field names and the other array is having a list of arrays where each array corresponds to row in table.How can i use these two arrays to create a list of JSON Objects. Is there any in built function. I am able to acheive this using map/reduce/ for -loop but this is impacting the performance if the second array is having more rows as we have traverse through each row.
I hope the following explains the use case better. Please share the sample code if possible.
Arr1=[field1,field2];
Arr2=[[1,2],[3,4],[5,6]];
Expected Output:
[
{
field1 :1 ,
field2: 2
},
{
field1 :3 ,
field2: 4
},
{
field1 :5 ,
field2: 6
}
]
You can use Array.map to map the elements
const mapFields = (arr1, arr2) => {
const mappedArray = arr2.map((el) => {
const mappedArrayEl = [];
el.forEach((value, i) => {
if (arr1.length < (i+1)) return;
mappedArrayEl[arr1[i]] = value;
});
return mappedArrayEl;
});
return mappedArray;
}
const Arr1 = ["field1","field2"];
const Arr2 = [[1,2],[3,4],[5,6]];
console.log(mapFields(Arr1, Arr2));
I have a array, which has the bunch of object, i would like to filter the object by 'name' value, again i would like to omit those object from another array of object using underscore.
I know that we can do using earch, but i am not getting the proper approach to do this both..
any one help me to do this?
example :
incoming array:
var incomingArray = [
{"name":"apple"},
{"name":"orange"},
{"name":"dog"},
{"name":"cat"},
{"name":"egle"}
];
filter keys:
var omit = ['orange' ,'dog'];
//i need to check whether 'orange' or 'dog' are exist, if so..
var filtered = _.filter(incomingArray, function(obj, i){
return obj.name === omit[i]['name'];//this is wrong i need to loop again how?
});
var anotherArray = [
{"name":"apple"},
{"name":"orange"},
{"name":"dog"},
{"name":"cat"},
{"name":"egle"}
]
return only the array without the omit like this:
var outgoingArray = [
{"name":"apple"},
{"name":"cat"},
{"name":"egle"} ]
how we could achieve this with proper approach?
demo
You were nearly there! Use indexOf to check that the name does not belong in the omit array:
var filtered = _.filter(incomingArray, function(obj) {
return omit.indexOf(obj.name) == -1;
});