Return r combinations from a group of n using Excel

Hi,

I have numeric co-variates in groups of 1, 2, 3, 4, 5, 6, etc.

Each group corresponds to a study I conducted

I'm trying to find all possible combinations of each study's group of co-variates - for example, if study 1 has corresponding co-variates 8, 3, 7.... then I want to find 3C2... so (8, 3) would be the first 2character group; (8, 7) would be the 2nd 2character group; and so on...

In Excel, I have my "studies" in row 1, and then the "groups of co-variates" corresponding to each study in row 2, and then I have the groups I want to combine them into (i.e., r=2, 3, 4, etc.) in the subsequent rows

I'm wondering if there is a macro I could use for this?

I'm attaching a sample of my data to give a better idea of exactly what I'm trying to achieve - I've manually created the combinations for "study 3".

My data is quite large, and I'm really hoping to be able to create a UDF whereby I can just enter the function name (e.g., Combinations), select the range (i.e., the single group of co-variates corresponding to the study), and then enter the "r" I need

Sorry if the above doesn't make sense, I'm quite new to VBA but think it may be my best option here! - feel free to ask any questions, all help is greatly appreciated as I really need to find a Macro to help me perform this function quickly!!!

Thank you in advance

Sample data.xlsx

Administrative Note:

Welcome to the forum.

We would very much like to help you with your query, however the thread title "Desperately need help writing Macro !!! " does not really convey what your request is about.

I have changed it for you since you are a new member.

In the future make sure that the title properly explains your request. Your title should be explicit and not be generic (this includes function names used without an indication of what you are trying to achieve).

Please see Forum Rule #1 about proper thread titles.

In response to PM (assuming your PM to me referenced this same problem). I might be able to help with something like this, but it is not the kind of programming that I do. There are probably others who are better at this than I am.

I set up this spreadsheet for generating permutations, if it will help: https://www.excelforum.com/tips-and-...thout-vba.html
I also would note that most algorithms that I see for generating permutations/combinations involve nested For..Next loops. Is there a specific part of generating these permutations/combinations that you are unsure of?

From what I have seen, the basic coding procedure is the same for permutations and combinations -- nested For..Next loops with appropriate choice of the limits, so I'm still not sure what you need help with. For example, the combinations of "choose 2 different from 3" is essentially:

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Or maybe your question is more about the incidental code that would go around the loops?