How to Use Arrays in Google Sheets

How to Harness the Power of Array Formulas in Google Sheets

If you work with data in spreadsheets, you‘ve likely encountered situations where you needed to perform the same calculation across multiple rows or columns. While you could painstakingly enter a formula into each individual cell, there‘s a much more efficient solution: array formulas.

What Are Array Formulas?

An array formula is a special type of formula that can perform multiple calculations on one or more sets of values, called "arrays." Arrays can include individual cells, ranges of cells, or even other array formulas. When you enter an array formula into a range of cells, it automatically expands to fill the entire range and returns an array of results.

This differs from a standard formula, which performs a calculation on a single value or cell reference and returns a single result. Array formulas allow you to work with multiple values simultaneously without having to enter a separate formula in each cell. Not only does this save time and reduce the risk of errors, but it also makes your spreadsheet more dynamic and easier to update.

How Do Array Formulas Work?

To enter an array formula, start by selecting the range of cells where you want the results to appear. Next, type the formula as you normally would, but instead of pressing Enter when you‘re done, hold down Ctrl+Shift (Windows) or Command+Shift (Mac) and press Enter. This tells Google Sheets to treat the formula as an array formula. You‘ll know it worked if curly braces { } appear around the formula in the formula bar.

For example, let‘s say you have a list of product prices in column B, and you want to calculate the sales tax for each product in column C. Without array formulas, you would need to enter a formula like =B2*0.08 in cell C2 and copy it down the column. But with an array formula, you can enter the formula once and have it automatically expand to fill the entire range.

To do this, select cells C2:C11, type =B2:B11*0.08, and press Ctrl+Shift+Enter. The formula will calculate the sales tax for each price in column B and return an array of results in column C. If you later add or remove products from the list, the array formula will automatically update to include the new values.

Benefits of Using Array Formulas

In addition to saving time and reducing errors, array formulas offer several other advantages over regular formulas:

  1. They allow you to perform complex calculations that would be difficult or impossible with standard formulas. For example, you can use array formulas to look up values in multiple criteria, filter and sort data, or create dynamic ranges.

  2. They make your spreadsheet more flexible and adaptable to change. Since array formulas automatically expand to fill the entire range, you can easily add or remove data without having to update individual formulas.

  3. They can help simplify your spreadsheet by reducing the number of formulas needed. Instead of having multiple formulas scattered throughout your sheet, you can often consolidate them into a single array formula.

  4. They can improve the performance and speed of your spreadsheet, especially when working with large datasets. Since array formulas perform calculations on entire ranges at once, they can be faster than multiple individual formulas.

Step-by-Step Guide to Creating Array Formulas

Now that you understand the basics of array formulas, let‘s walk through the process of creating one step-by-step:

  1. Select the range of cells where you want the array formula results to appear. The number of cells should match the expected output of your formula. For example, if your formula will return a single column of values, highlight a column range with the same number of rows as your input data.

  2. In the first cell of the selected range, type your formula as you normally would. Array formulas use standard Google Sheets functions and operators, so the syntax will be familiar. The key difference is that you‘ll reference entire ranges rather than individual cells.

  3. Instead of pressing Enter when you‘re done typing the formula, hold down Ctrl+Shift (Windows) or Command+Shift (Mac) and press Enter. This is called "array-entering" the formula. If done correctly, curly braces { } will appear around the formula in the formula bar, indicating it‘s an array formula.

  4. The array formula will automatically fill the selected range with results. Each cell will show the result of the formula for the corresponding input values. If you change any of the input values, the array formula will recalculate and update the results automatically.

Tips and Best Practices for Array Formulas

While array formulas are powerful tools, they can also be tricky to work with at times. Here are some tips and best practices to keep in mind:

  • Be careful when editing array formulas. If you try to edit an individual cell within an array formula range, you‘ll get an error. To make changes, select the entire range, click in the formula bar, make your edits, and array-enter the formula again.

  • Use named ranges in your array formulas to make them easier to read and maintain. For example, instead of referencing A2:A100, you could name that range "Prices" and use Prices in your formula.

  • Test your array formulas on a small sample of data before applying them to a large range. This will help you catch any errors or unexpected results early.

  • If your array formula is returning unexpected results, check for common issues like mismatched range sizes, incorrect syntax, or circular references. You can use the Formula Evaluation tool under the Help menu to step through the calculation and pinpoint the issue.

  • Don‘t nest too many functions within an array formula, as this can make it difficult to troubleshoot and slow down calculation. If your formula is getting too complex, try breaking it into smaller, simpler formulas.

  • Remember that array formulas calculate every cell in the referenced ranges, even if they‘re blank or contain errors. To avoid problems, use IF statements or other functions to handle empty cells gracefully.

Examples and Use Cases

Array formulas are useful in a wide variety of scenarios, from simple calculations to complex data analysis. Here are a few common examples:

  1. Calculating metrics: Use array formulas to calculate averages, sums, or other aggregate metrics across multiple ranges. For example, to calculate the average price of products in column B, you could use the formula =AVERAGE(B2:B100).

  2. Filtering and sorting: Array formulas can filter and sort data based on multiple criteria. For example, to filter a list of orders by date and status, you could use the formula =FILTER(A2:D100, B2:B100>=DATE(2023,1,1), C2:C100="Shipped").

  3. Looking up values: Array formulas can perform lookups based on multiple criteria, similar to a VLOOKUP with multiple conditions. For example, to look up a product price based on its name and category, you could use the formula =INDEX(PriceTable, MATCH(1, (ProductName=A2)*(Category=B2),0)).

  4. Dynamic ranges: Array formulas can create dynamic ranges that expand or contract based on the size of your data. For example, to sum the values in column B without including any empty cells, you could use the formula =SUM(B2:INDEX(B2:B100, COUNTA(B2:B100))).

  5. Conditional formatting: Array formulas can apply conditional formatting to a range based on complex criteria. For example, to highlight cells in column B that are greater than the average, you could use the formula =B2:B100>AVERAGE(B2:B100) in the conditional formatting rule.

These are just a few examples of what you can do with array formulas in Google Sheets. With a little creativity and experimentation, you can use them to tackle all kinds of data challenges.

Comparison to Regular Formulas

At this point, you might be wondering why you would use an array formula instead of a regular formula. After all, regular formulas can perform many of the same calculations and are often simpler to create and understand.

The main advantage of array formulas is their ability to work with multiple values and ranges simultaneously. This allows them to perform complex, multi-step calculations that would be difficult or impossible with regular formulas.

For example, let‘s say you have a table of sales data with columns for date, product, quantity, and price. You want to calculate the total revenue for each product, but only for sales that occurred in the last 30 days. With a regular formula, you would need to use a combination of SUMIFS and DATE functions, like this:

=SUMIFS(Price, Date, ">="&TODAY()-30, Product, A2)

This formula would need to be copied down the column for each product, with the cell reference in the last argument changing each time. And if you later add or remove products, you‘ll need to update the formulas to reference the correct cells.

With an array formula, you can perform the same calculation in a single formula that automatically expands to include all products:

=SUMIFS(Price, Date, ">="&TODAY()-30, Product, A2:A100)

This formula uses the same SUMIFS function, but references the entire Product column (A2:A100) instead of a single cell. When array-entered, it will calculate the total revenue for each product and return an array of results. If you add or remove products, the formula will automatically adjust to include the new data.

Of course, array formulas are not always the best solution. For simpler calculations or one-off analyses, regular formulas may be faster and easier to work with. But when you need to perform complex calculations across multiple ranges or automate repetitive tasks, array formulas can be a powerful tool.

Advanced Array Formula Techniques

Once you‘ve mastered the basics of array formulas, there are several advanced techniques you can use to take your skills to the next level:

  1. Using multiple criteria in array formulas: You can use the operator to combine multiple criteria in an array formula. For example, to sum cells in column B where the corresponding cells in column A equal "Yes" and column C is greater than 100, you could use the formula =SUM((A2:A100="Yes")(C2:C100>100)*B2:B100).

  2. Applying array formulas to non-contiguous ranges: Array formulas can reference non-contiguous ranges by using the comma operator. For example, to sum cells B2, B5, and B8, you could use the formula =SUM(B2,B5,B8). This can be useful for consolidating data from multiple ranges or sheets.

  3. Combining array formulas with other functions: Array formulas can be combined with other Google Sheets functions to create even more powerful calculations. For example, you could use an array formula with the FILTER function to extract data that meets multiple criteria, or with the QUERY function to perform SQL-like queries on your data.

  4. Creating dynamic arrays with the SEQUENCE function: The SEQUENCE function, introduced in 2022, allows you to generate arrays of sequential numbers. When combined with array formulas, this can be used to create dynamic ranges, perform complex lookups, or generate test data. For example, to generate an array of odd numbers from 1 to 100, you could use the formula =SEQUENCE(50,,1,2).

These are just a few examples of the advanced techniques you can use with array formulas. As you become more comfortable with the basics, experiment with combining array formulas with other functions and features to see what else you can create.

Conclusion

Array formulas are a powerful tool that every Google Sheets user should have in their toolbox. By allowing you to perform calculations on multiple ranges simultaneously, they can save you time, reduce errors, and make your spreadsheets more dynamic and adaptable.

In this guide, we‘ve covered the basics of array formulas, including how they work, the benefits of using them, and step-by-step instructions for creating them. We‘ve also looked at some tips and best practices for working with array formulas, as well as examples of common use cases.

Of course, mastering array formulas takes practice and experimentation. Don‘t be afraid to try new things and push the boundaries of what you can do with Google Sheets. With array formulas in your arsenal, you‘ll be able to tackle even the most complex data challenges with ease.