Arrays & Methods

Example demonstrating common array methods:

// Define an array of numbers
const numbers = [1, 2, 3, 4, 5];

// Use map() to create a new array with each number doubled
const doubled = numbers.map(num => num * 2);

// Use filter() to get numbers greater than 2
const filtered = numbers.filter(num => num > 2);

// Use reduce() to sum all numbers
const sum = numbers.reduce((acc, curr) => acc + curr, 0);

// Output results
console.log('Original:', numbers);
console.log('Doubled:', doubled);
console.log('Filtered (>2):', filtered);
console.log('Sum:', sum);
          

This code demonstrates:

• Creating arrays and accessing elements.
• Using map() for transformation.
• Filtering arrays with filter().
• Aggregating values using reduce().
• Logging results to the console.

Arrays: Ordered collections of values stored under a single variable. Arrays can hold any type of data including numbers, strings, objects, and even other arrays.

Common Array Methods:

• push() - Adds one or more elements to the end.
• pop() - Removes the last element.
• shift() - Removes the first element.
• unshift() - Adds elements to the beginning.
• map() - Creates a new array by applying a function to each element.
• filter() - Creates a new array with elements that pass a test.
• reduce() - Executes a reducer function on each element to reduce the array to a single value.
• forEach() - Executes a function for each element (no return).
• find() - Returns the first element that satisfies a condition.
• includes() - Checks if an array contains a value.
• sort() - Sorts the array elements.

These methods empower developers to manipulate arrays efficiently and elegantly in JavaScript.

• Processing lists of data such as user inputs, API responses, or database records.
• Transforming data for rendering in UI components like tables, lists, and charts.
• Filtering and sorting data for search and navigation features.
• Aggregating numerical data like totals, averages, and statistics.
• Building complex data pipelines using chained array methods.