REDUCE

REDUCE([initial_value], array, lambda(accumulator, value))

Returns the total value after reducing an array by applying a LAMBDA function.

[initial_value]	Sets the starting value for the accumulator.
array	An array to be reduced.
lambda	A nested LAMBDA function that takes two parameters.
accumulator	The value totalled up and returned as the final result.
value	The calculation applied to each element in the array

REMARKS

* This function was added in Microsoft 365.
* This function uses the LAMBDA function.
* This LAMBDA function must take two parameters.
* This LAMBDA function must have parameter names that do not include numbers.
* You can use the MAP function to return an identical array by applying a LAMBDA function to do some processing.
* You can use the SCAN function to return an identical array by applying a LAMBDA function to return some intermediate calculation values.
* This function was first released in July 2021.
* For the Microsoft documentation refer to support.microsoft.com
* For the Google documentation refer to support.google.com

	A	B	C	D	E
1	=REDUCE(1, C1:E2, LAMBDA(p_one, p_two, p_one+p_two)) = 22		1	2	3
2	=REDUCE(10, C1:E2, LAMBDA(p_one, p_two, p_one+p_two)) = 31		4	5	6
3	=REDUCE(1, C1:E2, LAMBDA(p_one, p_two, p_one*p_two)) = 720

1 - We would like to display the total of all the numbers, with an initial value of 1.
2 - We would like to display the total of all the numbers, with an initial value of 10.
3 - We would like to display the total value after multiplying all the numbers together.