# Excel MAP function

## Summary

The Excel MAP function transforms each value in one or more arrays into a new value by applying a specified LAMBDA function. This powerful feature enables complex array manipulations and custom calculations on array elements, offering a high degree of flexibility in data processing and analysis within Excel.
##### Syntax
```				```
=MAP(array1, [array2, …,] lambda_or_array<#>)
```
```
• array1, [array2, …,]: Arrays to be mapped. MAP can process multiple arrays simultaneously, provided they have the same dimensions.
• lambda_or_array<#>: A LAMBDA function that takes parameters matching the number of provided arrays and performs calculations on their elements. Alternatively, another array to be mapped can be provided.
##### Return value
An array where each element is the result of applying the LAMBDA function to corresponding elements from the input arrays.

## How to use

Define the array(s) you want to transform and specify a LAMBDA function that describes how each element should be processed. The LAMBDA function must accept as many parameters as there are arrays, and it must return a result based on those parameters.

## Examples

##### Simple MAP
Squaring Numbers Conditionally: Applying a condition to square numbers above a certain value.
```				```
=MAP(A1:C2, LAMBDA(a, IF(a > 4, a * a, a)))

```
```
This formula squares each number greater than 4 in the array A1:C2, leaving numbers 4 or less unchanged, showcasing MAP’s ability to conditionally transform array elements.
##### MAP for Logical Operations
Identifying Rows Where Both Conditions are True: Finding rows where two criteria in corresponding columns are met.
```				```
=MAP(TableA[Col1], TableA[Col2], LAMBDA(a, b, AND(a, b)))

```
```
This example checks two columns for logical TRUE and returns an array indicating where both conditions are satisfied, illustrating MAP’s utility in complex logical testing.
##### MAP with Multiple Criteria
Filtering Based on Size and Color: Using MAP to filter a dataset for specific attributes.
```				```
=FILTER(D2:E11, MAP(D2:D11, E2:E11, LAMBDA(s, c, AND(s = "Large", c = "Red"))))

```
```
Filters for rows where the “Size” is “Large” and the “Color” is “Red”, demonstrating how MAP can facilitate multi-criteria data filtering.
##### MAP for Arithmetic Transformations
Incrementing Each Array Element: Adding 1 to every item in an array.
```				```
=MAP({1, 2, 3}, LAMBDA(a, a + 1))

```
```
Increments each element of the array by 1, illustrating a basic arithmetic transformation using MAP.
##### MAP to Clean Data
Removing Non-numeric Values: Employing MAP to filter out non-numeric values from a dataset.
```				```
=MAP(B5:D16, LAMBDA(a, IF(ISNUMBER(a), a, "")))

```
```
Transforms a 12×3 array, replacing non-numeric values with blank strings, thereby cleaning the data for further analysis or visualization.