This guide covers everything you need to know about the Google Sheets MAP function, including its definition, syntax, use cases, and how to use it.
What is the MAP Function? How Does It Work?
The MAP function in Google Sheets helps you change a list of numbers or text based on a rule you set. You tell it what to do using something called a LAMBDA function. It goes through your list, applies the rule to each item, and gives you a new list with the changed items. It’s a way to easily make custom changes to your data.
At its core, the MAP function is a way to perform computations or operations on data sets. It’s essentially a way to say, “For each item in this list, apply this operation.” The result is a new array that reflects the changes made by the LAMBDA function.
The LAMBDA function used in conjunction with the MAP function serves as a blueprint for how each element in the array is to be manipulated. For example, if you want to double the values in a range of cells, you would create a LAMBDA function that multiplies each cell by 2. This LAMBDA function would then be fed into the MAP function along with the desired range.
It’s important to note that the LAMBDA function must have as many arguments as the number of input arrays given to the MAP function. The argument names in the LAMBDA function represent the current values being mapped in the array(s). If this condition is not met, an #N/A error is returned.
Furthermore, the MAP function does not support array results for mapped values. In other words, each input value should map to a single output value.
The syntax and arguments for the function are as follows:
MAP(array1, [array2, …], LAMBDA)
- array1: This is the first array or range that will be mapped. This is a required argument.
- array2, …: These are optional additional arrays or ranges that will also be mapped. You can add as many additional arrays as needed.
- LAMBDA: This is a LAMBDA function that’s applied to each value in the provided arrays to produce a new mapped value. The syntax for a LAMBDA function is LAMBDA(name1, [name2, …], formula_expression): The LAMBDA function should have exactly one name argument for each array passed, along with a formula_expression that uses these names. When the LAMBDA function is applied, these names resolve to the current values being mapped in the passed arrays.
Here are some important notes to remember about the syntax and arguments:
- The LAMBDA function you pass should accept exactly as many name arguments as the number of input arrays you give to MAP. If it doesn’t, you’ll get an #N/A error. These arguments correspond to the values in the input arrays that are being mapped to a new value.
- The values in the input arrays should map to a single value. Array results for mapped values aren’t supported.
Examples of How to Use the MAP Function
Here are some practical examples of how to use the MAP function in Google Sheets.
Example #1: Using MAP to Multiply Values in a Range
Assume you have a range A1:A5 with values 1, 2, 3, 4, and 5. You want to multiply each value in this range by 2. You can use the MAP function to achieve this. The formula would look like this:
=MAP(A1:A5, LAMBDA(x, x * 2))
The result will be an array with values 2, 4, 6, 8, and 10.
Example #2: Using MAP to Convert Text to Upper Case
Let’s say you have a range B1:B3 with names written in lower case: “john”, “paul”, “George”. You want to convert all these names to upper case. Here is how you can use the MAP function:
=MAP(B1:B3, LAMBDA(x, UPPER(x)))
The result will be “JOHN”, “PAUL”, “GEORGE”.
Example #3: Using MAP to Calculate Square of Numbers
Assume you have a range C1:C4 with values 2, 3, 4, 5. You want to calculate the square of each number in this range. You can use the MAP function as follows:
=MAP(C1:C4, LAMBDA(x, x^2))
The resulting array will be 4, 9, 16, 25.
Example #4: Using MAP to Convert Numbers to Text
Assume you have a range E1:E5 with numbers 100, 200, 300, 400, 500. You want to convert these numbers to text. You can use the MAP function as follows:
=MAP(E1:E5, LAMBDA(x, TEXT(x, “0”)))
The resulting array will be “100”, “200”, “300”, “400”, “500”.
Why Is MAP Not Working? Troubleshooting Common Errors
If you encounter issues while using the MAP function in Google Sheets, it can be due to a variety of reasons, each requiring a different solution. Understanding the common errors, their causes, and how to resolve them can help you make the most out of this powerful function.
Cause: This error typically occurs when one or more of the arguments provided to the MAP function is not valid. For example, you might be using a string where a number is expected, or you might be referring to a cell that contains an error.
Solution: Check the arguments you are passing to the MAP function. Ensure that each one is of the correct type and that the cells you are referring to do not contain any errors. Correct any issues you find and try the function again.
Cause: The #REF! error is often caused by a cell reference that is not valid. For example, you might be trying to reference a cell that has been deleted or a cell that does not exist.
Solution: Review the cell references in your MAP function and ensure that they are all valid. If you find any references to cells that have been deleted or do not exist, correct them and try the function again.
Cause: You might see this error if you are attempting to divide by zero within your MAP function. Division by zero is undefined, so Google Sheets returns an error.
Solution: Check your MAP function to see if you are performing any division operations. If you are, ensure that the denominator is never zero. You can do this by adding a condition to check if the denominator is zero before performing the division.
Cause: This error usually means that Google Sheets does not recognize the function name. It might be due to a spelling mistake in the function name, or you might be trying to use a function that does not exist.
Solution: Check the spelling of the MAP function in your formula. The correct spelling is ‘MAP’.
Cause: The #N/A error indicates that a value is not available. This can happen if you are trying to map a value that is not present in the data you are working with.
Solution: Review the values you are trying to map and the data you are mapping from. If the value is not present in the data, you will need to either add it or adjust your function to work without it.
Cause: This is a generic error that can occur for a variety of reasons. It typically means that something is wrong with your MAP function, but it does not specify what the issue is.
Solution: Debug your MAP function by checking each part of it individually. Make sure that all arguments are valid, that all cell references are correct, and that there are no other issues. Once you have identified and fixed the problem, your MAP function should work correctly.
Using MAP With Other Google Sheets Functions
Combining MAP with other Google Sheets functions can enhance your data analysis and manipulation capabilities. The MAP function can be used in conjunction with other Google Sheets functions.
Usage: The FILTER function is used to filter a range of cells based on certain conditions. When used with MAP, it allows you to apply the same conditions to multiple ranges or arrays.
Example: If you have data in ranges A1:A3 and B1:B3, and you want to filter out the cells in both ranges that are less than 5, you can use the following formula:
=FILTER(MAP(A1:A3, B1:B3, IF(@cellA < 5, “”, @cellA)), LEN(MAP(A1:A3, B1:B3, IF(@cellA < 5, “”, @cellA))) > 0)
Usage: The COUNT function is used to count the number of cells that contain numbers in a range. When combined with MAP, it allows you to count the number of cells that meet certain conditions across multiple ranges or arrays.
Example: If you have data in ranges A1:A3 and B1:B3 and want to count the number of cells in both ranges that are greater than 10, you can use the following formula:
=COUNT(MAP(A1:A3, B1:B3, IF(@cellA > 10, @cellA, “”)))
This formula will count the number of cells in the two ranges that are greater than 10 and return the result.
For more details on the MAP function, check out the official documentation at the Google Docs Editors Help Center.