LAMBDA for custom functions in Excel - Cell-by-Cell Formula Trace

Sample Data

Column A has numbers. Column B uses a LAMBDA function to double each number from column A.

Cell	Value
A1	5
A2	10
A3	15
B1	=LAMBDA(x, x*2)(A1)
B2	=LAMBDA(x, x*2)(A2)
B3	=LAMBDA(x, x*2)(A3)

Formula Trace

=LAMBDA(x, x*2)(A2)

Step 1: LAMBDA(x, x*2)

Step 2: LAMBDA(x, x*2)(A2)

Step 3: 10 * 2

Cell Reference Map

   A    B
1  5    =LAMBDA(x, x*2)(A1)
2 10 -> =LAMBDA(x, x*2)(A2)
3 15    =LAMBDA(x, x*2)(A3)

Cells in column B use the LAMBDA function to double the values from column A.

Result

   A    B
1  5    10
2 10    20
3 15    30

Column B shows the doubled values of column A using the LAMBDA function.

Sheet Trace Quiz - 3 Questions

What does the LAMBDA function in cell B2 do with the value in A2?

A It doubles the value 10 to 20

B It adds 2 to the value 10

C It returns the value 10 unchanged

D It halves the value 10 to 5

Key Result

LAMBDA defines a custom function with parameters and is called immediately with arguments.