Extract Unique Letters from a Word in Google Sheets

Mastering Unique Letter Extraction in Google Sheets

Imagine working on a word puzzle in Google Sheets where every cell reflects a unique letter from a word like "TRILLION," in the order of their first appearance. 📜 Sounds exciting, right? But achieving this isn’t as simple as it seems. Unique letters need to be identified while keeping their original sequence intact.

Many users quickly turn to functions like UNIQUE or SORT in Google Sheets, only to find that they don’t behave as expected. These functions are great for sorted arrays but falter when preserving the order of first occurrences. The challenge lies in combining these functions effectively to meet the goal.

Picture this: You update the word to "BANANA" and want the result to instantly reflect "BAN" without losing any original order. 🕵️‍♀️ This ensures your spreadsheet remains dynamic and adaptable for various puzzles. No manual work, just clean automation.

In this guide, we’ll explore how to use Google Sheets formulas creatively to solve this problem. By the end, you’ll know how to extract unique letters in their original order effortlessly, adding a new layer of functionality to your Sheets experience. 🚀

Unpacking Solutions for Extracting Unique Letters

The first solution, implemented in Google Apps Script, automates the process of extracting unique letters while maintaining their original order. It works by looping through each character of the input word (e.g., "TRILLION") and checking if the letter is already in the result string. If it isn’t, the letter is added, ensuring that duplicates are skipped. This script dynamically updates the spreadsheet output, placing each unique letter into separate cells horizontally. For example, updating the word in cell A1 to "BANANA" instantly updates the output to "BAN". This automation makes it ideal for repetitive tasks, such as word puzzles. 🧩

The formula-based solution leverages Google Sheets functions like SPLIT, ARRAYFORMULA, and TEXTJOIN. These functions collectively transform the word into individual letters, identify unique ones, and combine them into a single result. Notably, MATCH plays a key role by comparing each letter’s position to determine if it is the first occurrence, ensuring duplicates are skipped. The formula is dynamic and updates instantly when the input word changes. This approach is particularly suited for users unfamiliar with scripting but needing a quick and effective solution.

The third solution, written in standalone JavaScript, focuses on flexibility for diverse environments, including front-end web applications. The function iterates through the input string and builds an array of unique characters. By returning the unique characters as a new string, it allows seamless integration with user interfaces or other backend processes. For instance, a web-based word puzzle app could use this function to display unique letters from any user-provided input dynamically. Its simplicity and modularity make it a robust choice for developers. 🌐

Finally, unit tests ensure each solution works correctly. Testing with frameworks like Mocha/Chai validates both edge cases and regular inputs, such as handling empty strings or words with all identical letters. For example, when testing with "AAAAA," the output "A" confirms that duplicates are effectively handled. Adding error handling safeguards against invalid inputs, ensuring reliability. By combining these solutions with tests, users and developers alike gain confidence in their accuracy and adaptability. Together, these approaches demonstrate how both technical tools and creative thinking can address real-world challenges like extracting unique letters. 🚀

// Function to extract unique letters from a string in order of appearancefunction extractUniqueLetters() {  var sheet = SpreadsheetApp.getActiveSpreadsheet().getActiveSheet(); // Access the active sheet
  var inputCell = sheet.getRange("A1").getValue(); // Get the word from cell A1
  var uniqueLetters = "";
  for (var i = 0; i < inputCell.length; i++) {
    if (!uniqueLetters.includes(inputCell[i])) {
      uniqueLetters += inputCell[i];
    }
  }
  var outputRange = sheet.getRange(1, 2, 1, uniqueLetters.length);
  var outputArray = uniqueLetters.split("");
  outputRange.setValues([outputArray]); // Write unique letters horizontally
}

=ARRAYFORMULA(TEXTJOIN("", TRUE,
IFERROR(IF(MATCH(SPLIT(A1, ""), SPLIT(A1, ""), 0) = ROW(SPLIT(A1, "")),
SPLIT(A1, ""),
""),
""
)))

// Function to get unique letters in the order they appearfunction getUniqueLetters(word) {  let unique = [];
  for (let char of word) {
    if (!unique.includes(char)) {
      unique.push(char);
    }
  }
  return unique.join("");
}
// Example Usage:
console.log(getUniqueLetters("TRILLION")); // Output: TRILON

const { expect } = require("chai");
describe("getUniqueLetters", function () {
  it("should return TRILON for TRILLION", function () {
    expect(getUniqueLetters("TRILLION")).to.equal("TRILON");
  });
  it("should return BAN for BANANA", function () {
    expect(getUniqueLetters("BANANA")).to.equal("BAN");
  });
});

Efficient Methods to Extract Unique Letters in Order

An often-overlooked aspect of extracting unique letters in order is the scalability of your solution. When working with dynamic inputs, like user-generated words in a spreadsheet or an application, ensuring the method handles a wide range of cases—such as long words or unusual characters—is essential. For instance, processing "MISSISSIPPI" efficiently to get "MISP" without slowing down is a key challenge, especially when this needs to scale across multiple sheets or datasets. 📝

Another important consideration is the adaptability of the solution. Using advanced techniques like array processing ensures your logic works across different environments. In Google Sheets, built-in array functions like ARRAYFORMULA and SPLIT allow you to automate repetitive tasks without scripts. These functions make it easier to create templates for puzzles or educational games, enabling quick duplication while retaining functionality. This adaptability reduces maintenance time and ensures a smooth experience for users. 📊

Lastly, optimization ensures your solution is both fast and resource-efficient. For example, in scripting environments like JavaScript, iterating through the input word once with a single loop significantly improves performance over repeated checks. Similarly, leveraging TEXTJOIN in Sheets minimizes formula complexity. These techniques ensure that your solution remains robust, even as the dataset grows in size or complexity. Whether you're managing a single puzzle or a full-scale project, optimized solutions offer long-term benefits. 🚀