Using JavaScript, sift through various elements in a large array and extract only specific

Question

Using JavaScript, sift through various elements in a large array and extract only specific

I have retrieved an array containing 2400 objects from our server, totaling about 7MB in size, and I need to extract specific values from it. Currently, I am using a combination of the filter and slice methods:

 const keyword = 'whatever word';
 const recommendList = bigArray.filter(item => item.name.includes(keyword)).slice(0, 5);

I understand that the filter method iterates through all elements in the array which may impact the performance of my app (React Native) due to the large data set. Is there an alternative approach to filter the array for certain values without iterating through all elements?

javascript arrays

Answer 1

Answer №1

If you want to break the loop when you reach the 5th element, you can follow this approach:

const keyword = 'v';
const bigArray = ['a','v','a','v','a','v','a','v','a','v','a','v','a','v','a','v','a','v'];
const recommendList = [];
for (let i=0; i<bigArray.length; i++) {
  if (recommendList.length == 5) { 
    break; 
  }
  
  if (bigArray[i].includes(keyword)) {
    recommendList.push(bigArray[i]);
  }
}
console.log(recommendList);

If you prefer not to use lambda operations, you can utilize methods like some or find which will stop iterating after finding the first true response.

const bigArray = [{
    "name": "a"
  },
  {
    "name": "v"
  },
  {
    "name": "a"
  },
  // more objects...
];

const keyword = 'v';
const recommendList = [];

bigArray.some(obj => {
  if (obj.name.includes(keyword)) {
    recommendList.push(obj)
  }
  return recommendList.length === 5;
})

console.log(recommendList);

Answer 2

If you want to break the loop when you reach the 5th element, you can follow this approach:

const keyword = 'v';
const bigArray = ['a','v','a','v','a','v','a','v','a','v','a','v','a','v','a','v','a','v'];
const recommendList = [];
for (let i=0; i<bigArray.length; i++) {
  if (recommendList.length == 5) { 
    break; 
  }
  
  if (bigArray[i].includes(keyword)) {
    recommendList.push(bigArray[i]);
  }
}
console.log(recommendList);

If you prefer not to use lambda operations, you can utilize methods like some or find which will stop iterating after finding the first true response.

const bigArray = [{
    "name": "a"
  },
  {
    "name": "v"
  },
  {
    "name": "a"
  },
  // more objects...
];

const keyword = 'v';
const recommendList = [];

bigArray.some(obj => {
  if (obj.name.includes(keyword)) {
    recommendList.push(obj)
  }
  return recommendList.length === 5;
})

console.log(recommendList);

Answer 3

Answer №2

let term = 'specific term';
let suggestions = [];
for (let j=0; j < largeData.length; j++) {
  if (suggestions.length >= 5) 
    break;

  const element = largeData[j];
  if (element.title.includes(term)) 
    suggestions.push(element);
}

Answer 4

let term = 'specific term';
let suggestions = [];
for (let j=0; j < largeData.length; j++) {
  if (suggestions.length >= 5) 
    break;

  const element = largeData[j];
  if (element.title.includes(term)) 
    suggestions.push(element);
}

Answer 5

Answer №3

To enhance efficiency, consider processing the array as a seamless sequence.

Check out this example built on the iter-ops library:

import {pipe, filter, take} from 'iter-ops';

const result = pipe(
    largeArray,
    filter(item => item.name.includes(keyword)),
    take(5)
);

console.log('matches:', [...result]);

This method avoids unnecessary iterations and stops once the first 5 matches are found.

Answer 6

To enhance efficiency, consider processing the array as a seamless sequence.

Check out this example built on the iter-ops library:

import {pipe, filter, take} from 'iter-ops';

const result = pipe(
    largeArray,
    filter(item => item.name.includes(keyword)),
    take(5)
);

console.log('matches:', [...result]);

This method avoids unnecessary iterations and stops once the first 5 matches are found.

Answer 7

Answer №4

When considering this scenario, my belief is that using a filter operation (with the complexity being O(n)) would be the optimal solution to minimize any performance impact.

For example, if you were to filter out only 1500 values from a total of 2400 objects, then you would be left with a result set containing just 1500 objects, while the remaining 900 objects would go unused. In such cases, it becomes essential to iterate through the collection at least once.

Answer 8

When considering this scenario, my belief is that using a filter operation (with the complexity being O(n)) would be the optimal solution to minimize any performance impact.

For example, if you were to filter out only 1500 values from a total of 2400 objects, then you would be left with a result set containing just 1500 objects, while the remaining 900 objects would go unused. In such cases, it becomes essential to iterate through the collection at least once.

Using JavaScript, sift through various elements in a large array and extract only specific

Answer №1

Answer №2

Answer №3

Answer №4

Similar questions

Customizing the toString method within an object's definition

Find all Mondays occurring within a specified date range using Moment.js

What is causing the loss of context for 'this' in the latest Angular 1.5 components?

Send the form to the webpage and display various div elements based on the entered information

Different methods for conserving memory while comparing arrays instead of using np.newaxis()

Execute various settimeout or display functions on various elements of a webpage

Merging elements in an array according to specific rules and documenting the results

A guide on incorporating and utilizing third-party Cordova plugins in Ionic 5

Making an AJAX request to a different domain

Node.js: The choice between returning the original Promise or creating a new Promise instance

Loading suggestions ahead of time in Vuetify's autocomplete feature

What is the best class to implement in my jQuery code?

Guide on filling out multiple forms with just one form

Determine in React whether a JSX Element is a descendant of a specific class

Guide on reading input from the standard input and storing it into a two-dimensional Python array containing only integers

Include category to the smallest element

The window.open() function in Microsoft Edge is failing to respect specified width and height parameters, causing it to

Unveiling Fresh URLs within an iFrame

Repurposing components like custom text inputs, spans, and more in ASP.NET MVC using Razor

Filtering Objects in Javascript: A Step-by-Step Guide