
The `MUNIT` function in Excel is used to generate a unit matrix or identity matrix. An identity matrix is a square matrix with ones on the main diagonal and zeros elsewhere.
Here’s how you can use the `MUNIT` function:
Syntax
MUNIT(n)
- n: This argument specifies the number of rows and columns in the identity matrix. The result will be an n x n matrix.
Steps to Use MUNIT
- Select a Range:
- First, select an n x n range in your Excel sheet where you want to display the identity matrix. For example, if you want a 3×3 matrix, select a 3×3 range of cells.
- Enter the Formula:
- While still having your range selected, type the formula `=MUNIT(n)`, where `n` is the size of the identity matrix you want. For a 3×3 identity matrix, you would enter `=MUNIT(3)`.
- Array Formula:
- Since `MUNIT` returns an array, you must enter it as an array formula.
- If you are using Excel 365 or Excel 2019, just press Enter after typing your formula. Excel automatically handles dynamic array formulas.
- In earlier versions of Excel, you need to press Ctrl + Shift + Enter instead of just Enter after typing the formula. This will place curly brackets `{}` around your formula, indicating it’s an array formula.
- Result:
- Excel will fill the selected range with the identity matrix based on the specified size.
Example
If you want to create a 3×3 identity matrix, you would:
- Select a 3×3 range of cells in Excel.
- Enter `=MUNIT(3)`.
- Press Ctrl + Shift + Enter (for versions prior to Excel 365/2019) or just Enter if you are using one of the newer versions.
This will populate the selected range with:
1 0 0
0 1 0
0 0 1
Using the `MUNIT` function is straightforward once you understand the basics of array formulas in Excel. Remember that you need to select a range that matches your desired matrix size before entering the function.