When you want to access the contents of a cell, use the curly braces: A{1} etc. (n - k)!) You're not really going to be able to do this. Matrix C has k columns and n!/(k! See Variable-Sizing Restrictions for Code Generation of Toolbox Functions (MATLAB Coder). Here, n= 3, k=n-1=2 (always k=n-1). When you post the code you want to apply, more detailed suggestions are possible. Matrix C has k columns and n!/(k! C = nchoosek(v,k), where v is a row vector of length n, creates a matrix whose rows consist of all possible combinations of the elements of v taken at a time. And why does the variable a appear in the first and second input? '; toc; %' Elapsed time is 12.523955 seconds. Learn more about nchoosek, combinations, vector C = nchoosek(n,k) where n and k are nonnegative integers, returns . There you find FEX: VChooseK.mex.I think, this is the fastest implementation, but it needs a compilation. nchoosek accepts scalar variables as 2nd input only. Or you can download the pre-compiled files and install the required runtime libraries of MSVC 2008. The MATLAB documentation for nchoosek says. (n - k)!) nchoosek help. Octave and Matlab âwatâ matrix/vector inconsistencies. 1. rows and n columns. C = nchoosek(v,k) returns a matrix containing all possible combinations of the elements of vector v taken k at a time. matlab matrix vector. nchoosek(1:100,10) is absolutely vast, far bigger than any typical machine could hold in memory. C = nchoosek(n,k) C = nchoosek(v,k) Description. C = nchoosek(v,k) is only practical for situations where length(v) is less than about 15. Nchoosek is not written in any way to allow you to choose only some reduced subset. 2. In fact, the set of 200 bit binary numbers has a HUGE number of subsets with 5 bits set. How can I apply this function to all the rows of the matrix or at least, for the above vector. C = nchoosek(v,k) returns a matrix containing all possible combinations of the elements of vector v taken k at a time. I've tried this with perms,nchoosek,repelem,repmat,for-loops,unique,matrix concatenations,everything but i couldn't be able to find and algorithm. I want to use nchoosek function to find the combinations of (total number of 1's in a row) -1. Therefore the readers cannot guess, what you expect as output. Searching the FEX is always a good idea. In this case, x can have type int64 or uint64. I was kind of surprised, until I looked at the code for NCHOOSEK (by typing type nchoosek in the MATLAB command window). rows, where n is length(v).In this syntax, k must be a nonnegative integer. This is the number of combinations of things taken at a time. When the first input, x, is a vector, nchoosek treats it as a set. >> tic; pairs = nchoosek(1:N,2). Matlab matrix with fixed sum over rows. rows, where n is length(v).In this syntax, k must be a nonnegative integer. 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