Lodash _.sortedUniqBy() Array Method

Posted in lodash Tutorial

Updated on Feb 24, 2024

By Mari Selvan

👁️ 35 - Views

⏳ 4 mins

💬 1 Comment

Photo Credit to CodeToFun

🙋 Introduction

In the realm of JavaScript development, efficiently managing arrays is paramount. Enter Lodash, a robust utility library that offers a myriad of functions to simplify array manipulation. Among these functions lies the _.sortedUniqBy() method, a powerful tool for eliminating duplicate values from sorted arrays based on a specific criterion. This method enhances code readability and performance, making it indispensable for developers dealing with sorted data.

🧠 Understanding _.sortedUniqBy()

The _.sortedUniqBy() method in Lodash is designed to remove duplicate elements from a sorted array while allowing customization based on a provided iteratee function. This enables developers to specify the criteria by which uniqueness is determined, offering flexibility and precision in data manipulation.

💡 Syntax

syntax.js

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_.sortedUniqBy(array, [iteratee])

array: The sorted array to process.
iteratee (Optional): The function invoked per iteration.

📝 Example

Let's delve into a practical example to grasp the functionality of _.sortedUniqBy():

example.js

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const _ = require('lodash');

const sortedArray = [1, 2, 2, 3, 3, 3, 4, 5, 6];
const uniqueArray = _.sortedUniqBy(sortedArray);

console.log(uniqueArray);
// Output: [1, 2, 3, 4, 5, 6]

In this example, the sortedArray is processed by _.sortedUniqBy(), resulting in a new array containing only unique elements in sorted order.

🏆 Best Practices

Understanding Sorted Arrays:

Ensure that the input array is sorted before applying _.sortedUniqBy(). This method is optimized for sorted arrays, and applying it to unsorted data may yield unexpected results.
example.js
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```
const unsortedArray = [3, 1, 2, 2, 4, 3];
const sortedUniqueArray = _.sortedUniqBy(_.sortBy(unsortedArray));

console.log(sortedUniqueArray);
// Output: [1, 2, 3, 4]
```

Define Custom Criteria:

Utilize the iteratee parameter to define custom criteria for uniqueness. This allows you to tailor the behavior of _.sortedUniqBy() according to your specific requirements.

example.js

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const arrayOfObjects = [
    { id: 1, value: 'apple' },
    { id: 2, value: 'banana' },
    { id: 3, value: 'apple' },
];

const uniqueObjects = _.sortedUniqBy(arrayOfObjects, obj => obj.value);

console.log(uniqueObjects);
// Output: [{ id: 1, value: 'apple' }, { id: 2, value: 'banana' }]

Performance Considerations:

Keep in mind the performance implications when working with large datasets. The _.sortedUniqBy() method offers optimized performance for sorted arrays, making it ideal for handling large volumes of data efficiently.
example.js
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```
const largeSortedArray = /* ...generate a large sorted array... */;

console.time('sortedUniqBy');
const uniqueValues = _.sortedUniqBy(largeSortedArray);
console.timeEnd('sortedUniqBy');

console.log(uniqueValues);
```

📚 Use Cases

Removing Duplicate Entries:

_.sortedUniqBy() is particularly useful when dealing with sorted datasets containing duplicate entries. By removing duplicates, you can ensure data integrity and streamline subsequent operations.
example.js
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```
const sortedDataWithDuplicates = [10, 20, 20, 30, 30, 40, 50];
const uniqueData = _.sortedUniqBy(sortedDataWithDuplicates);

console.log(uniqueData);
// Output: [10, 20, 30, 40, 50]
```

Data Normalization:

In scenarios where data normalization is necessary, _.sortedUniqBy() can be employed to condense redundant information, facilitating cleaner and more concise data representation.

example.js

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const normalizedData = [
    { id: 1, category: 'fruit' },
    { id: 2, category: 'vegetable' },
    { id: 3, category: 'fruit' },
];

const uniqueCategories = _.sortedUniqBy(normalizedData, obj => obj.category);

console.log(uniqueCategories);
// Output: [{ id: 1, category: 'fruit' }, { id: 2, category: 'vegetable' }]

Performance Optimization:

By leveraging the optimized performance of _.sortedUniqBy() for sorted arrays, you can enhance the efficiency of your code, especially when dealing with large datasets or performance-sensitive applications.
example.js
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```
const largeDataset = /* ...fetch data from API or elsewhere... */;
const sortedUniqueData = _.sortedUniqBy(_.sortBy(largeDataset));

console.log(sortedUniqueData);
```

🎉 Conclusion

The _.sortedUniqBy() method in Lodash offers a powerful solution for removing duplicate elements from sorted arrays with customizable uniqueness criteria. Whether you're working with sorted datasets or striving for optimal performance, this method provides a versatile tool for array manipulation in JavaScript.

Unlock the potential of sorted array manipulation with _.sortedUniqBy() and elevate your JavaScript development experience!