Summing over indices

[isabel_b]

Hello, 

I am trying to do a sum over indices and am unsure how to go about it. I've tried the Multi-Row formula, but it is pretty cumbersome and has been returning a 0 value. I would like to perform something along the lines of the following:

Where 'n' corresponds to the row number, and 'i' is the current (active) row. My data looks like this:

n	P	gamma
1	0.05	.05
2	0.10	.05
3	0.10	.05
4	0.15	.1
5	0.20	.15
6	0.25	.2
7	0.10	.2
8	0.05	.2

Thanks for your help!

[gc]

Well if someone can figure this one out using Alteryx tools, I have a star ready and waiting for them!

Personally, I'd try  busting out some "R" code and use the R tool on the Developer tab to get this done.

[jdunkerley79 · Accepted solution]

Assuming I have understood it correctly:

Should do what you want.

Use and Append fields to create a Cartesian product (i.e. have all 8 rows for every row)

Compute the expression (post a little rearrangement)

Sum the values grouped for each i