# How many times does each combination of numbers appear?

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Jake Mcgee on 21 Oct 2019
Edited: per isakson on 21 Oct 2019
Let's say I ran randi(1-40) to produce 5 columns and 100 rows Would I be able to get it to tell me how many times, 1 and 2, for example, come up in the same row. Then if not how may times another combination would come up like 3 and 4 for example? Thanks everyone for any help

Guillaume on 21 Oct 2019
randi is just a function to generate random numbers. The only thing you get out of it is the random numbers. But yes, you can easily write code to get the histogram of the random numbers generated.
Jake Mcgee on 21 Oct 2019
please can you show me an example, i am relativly new to matlab but if you wrote a wuick small example im sure i could figure it out.
Thank you so much for your time

per isakson on 21 Oct 2019
Edited: per isakson on 21 Oct 2019
"get it to tell" depends on what the little word "it" refers to. The function randi() cannot tell that.
Try this as a start
%%
M = randi([1,5],100,5);
has_12 = arrayfun( @(jj) all( ismember( [1,2], M(jj,:) ) ), (1:size(M,1)) );
has_34 = arrayfun( @(jj) all( ismember( [3,4], M(jj,:) ) ), (1:size(M,1)) );
has = has_12 & has_34;
>> sum(has)
ans =
10
>>
In this case, ten out of one hundred rows has 1,2,3 and 4,