Lodash is a JavaScript library that works on the top of underscore.js. Lodash helps in working with arrays, collection, strings, objects, numbers etc.
The _.flatMap() method creates a flattened array of values by running each element in collection through iteratee and flattening the mapped results.
Syntax:
_.flatMap(collection, iteratee)
Parameters: This method accepts two parameters as mentioned above and described below:
- collection: This parameter holds the collection to iterate over.
- iteratee: This parameter holds the function invoked per iteration.
Return Value: This method returns the new flattened array.
Example 1: Here, const _ = require(‘lodash’) is used to import the lodash library in the file.
javascript
// Requiring the lodash library const _ = require( "lodash" ); // Original array var user1 = ([35, 47, 58, 69, 94, 13, 72]); // Use of _.flatMap() method let gfg1 = _.flatMap(user1, function duplicate(n) { return [n, n]; }) // Printing the output console.log(gfg1); |
Output:
[ 35, 35, 47, 47, 58, 58, 69, 69, 94, 94, 13, 13, 72, 72 ]
Example 2:
javascript
// Requiring the lodash library const _ = require( "lodash" ); // Original array var user1 = ([3.5, 4.7, 5.8, 6.9, 9.4, 1.3, 7.2]); var user2 = ([3, 4, 5, 9, 9, 1, 7]); // Use of _.flatMap() method let gfg1 = _.flatMap(user1, function duplicate(n) { return [n, n]; }) let gfg2 = _.flatMap(user2, function duplicate(n) { return [n, n]; }) // Printing the output console.log(gfg1); console.log(gfg2); |
Output:
[ 3.5, 3.5, 4.7, 4.7, 5.8, 5.8, 6.9, 6.9, 9.4, 9.4, 1.3, 1.3, 7.2, 7.2 ] [ 3, 3, 4, 4, 5, 5, 9, 9, 9, 9, 1, 1, 7, 7 ]
Note: This code will not work in normal JavaScript because it requires the library lodash to be installed.