# matlab permutation with repetition

s(1:N - 1) = L; 6.3 Permutations and Combinations Permutations De nition 1. There are 2 kinds of permutations: Permutations with Repetition - You can re-use the same element within the order, such as in the lock from the previous question, where the code could be "000". In MATLAB I can simply do this: ... How to generate all permutations with repetition of a given vector in MatLAB. 1:3},2) % returns the 4-by-2 cell array The permutation of a number of objects is the number of different ways they can be ordered: the position is important. Undefined variable/function, You may receive emails, depending on your. 7 7 7 99 Permutations with Repetition. It is clear from the example that this submission generates what is sometimes called "permutations with repetitions": If this submission truly calculated the combinations then the sets {0,0,1}, {0,1,0}, and {1,0,0} are all equivalent, and would not all appear in the output shown in the example. same type as V. If V is empty or N is 0, M will be empty. You can also select a web site from the following list: Select the China site (in Chinese or English) for best site performance. We want all the possible permutation without repetition. s(1:k-1) = {ones(1, nX)}; with 3 input variables: M = permn(V,N,K) returns only the K-ths Purpose of use something not wright Comment/Request I ha padlock wit 6 numbers in 4 possible combinations. If all the objects are arranged, the there will be found the arrangement which are alike or the permutation which are alike. allcomb, permpos on the File Exchange. V can be any type of array (numbers, cells etc.) Very helpful to solve my actual problem. [1x3 double] [1x3 double] Solution. It really helped me solve some problems. The permutations of the pairs does not matter %-----1- n should be even. The update incorporates his excellent solution to this potential problem. Thank you very much :). random permutation with repetition for > 2000 elements Hi randperm is for permutations WITHOUT repetition. Thanks! However, I would like to avoid identical permutations such as these. I also have another program but it's only works with 0 and 1. Field_A = [50 60 70 80] Field_B = [ 10 30 90 100] Field_C = [100 500 700 1000] Only one value should be selected from each field to create all possible answers (Vector of three elements). M = permn([1 2 3],2) % returns the 9-by-2 matrix: Best Answer. Find the treasures in MATLAB Central and discover how the community can help you! permutations. randperm is for permutations WITHOUT repetition. Find the treasures in MATLAB Central and discover how the community can help you! 2- a unique combination of n/2 outputs of nchoosek(n ... Find the treasures in MATLAB Central and discover how the community can help you! I am using matlab 2016b and try to find al the permutations with repetition. X = permute(X, [1:i-1, i+1, i]); ), permn - permutations with repetition a=zeros(l^N,N); 2 1 3 3 Yet I bounce very quickly against maximum variable size for Matlab. Any idea? 99 99 7 99 Reload the page to see its updated state. X = X(:); https://www.mathsisfun.com/combinatorics/combinations-permutations.html Here, all the permutations are generated in 1 go and then stored in the huge allstrs array. Lets take a small example: I=3:6 and I want to have permutations of 3 with repetition: We should have a list with 4^3 possible outcomes. 99 99 99 7 http://mathworld.wolfram.com/Combination.html, https://www.mathsisfun.com/combinatorics/combinations-permutations.html, @Marc, thanks for your interest and suggestions for improvement. Renamed file into PERMN, fixed small bug, extended help section. In this formula, n is the number of items you have to choose from, and r is how many items you need to choose, in a situation where repetition is allowed and order matters. Permutations without repetition. X = fliplr(reshape(cat(N+1,X{:}),[],N)) ; Some of them are: Jos (10584) (2021). This is particulary useful when you only need a few Thanks Roger! * If the order doesn't matter, it is a Combination. Please read the help before using. You saved my day thanks a lot! The di erent orders for elements a;b, and c are If you had asked for, say, all permutations of five numbers chosen out of a larger number like ten, I would have had to do more work above. I'd like to know how combine different vector in order to obtain different matrix. Unable to complete the action because of changes made to the page. %fill Y directly: A great work. The matrix P will now contain all possible permutations of five elements selected out of v. There will be 720 rows and 5 columns. is this possible? i put in excel every combination (one by one, put every single combination with "duplicate values" turned ON) possible and I get 1080 different combinations. Accelerating the pace of engineering and science. for iC = 2:N This is an example of permutation with repetition because the elements are repeated and their order is important. combinations. nX = numel(X); I'm actually using these permutations as the design space for an optimization problem so I need to check my cost function for every permutation … A must have. I am very surprised this is not a build in function. 2 3 C = cell(1, N); for i=1:N But it gives me an error saying: Undefined function or variable 'permn'. Inlining and simplyfying NDGRID leads to (REPMAT can be omitted then): Retrieved January 1, 2021. any idea of how to get the combinations without repetition of previous combinations, and without re-using the elements in a a selection? Combinations with repetition. A permutation is an ordering of a set of objects. See also perms, nchoosek I don't use combinatorics very much but I always wonder why matlab doesn't cover it esplicitly. Based on your location, we recommend that you select: . A permutation of a set of (distinct) objects is an ordering of the objects in row. Lets take a small example: I=3:6 and I want to have permutations of 3 with repetition: We should have a list with 4^3 possible outcomes. All combinations from a set of rows without repetition of elements. end, where n= number of elements (as N here) and Matlab combinations with repetition. % Check with permn using two inputs Incorporated the functionality of permnsub, allowing for returning a subset rather than all permutations as well. H1-line, help, history, comments in the code, efficient. but it's limited to 10. i need 20. % This has inverse order for the combinations as you had, easy to change. for i = 1:k Each of these will produce successive outputs of the combs/perms of K elements taken from the set 1:N. See the screenshot for an example. % 14 15 14 be empty. function result=seqrep(V,N) Accelerating the pace of engineering and science. [1x3 double] 'hello!' I forgot the "password". It saved me much time! All combinations from a set of rows without repetition of elements. Can someone tell me how I can call this in my own MatLab program. I assume you mean that all matrix entries are to be non-negative integers and that, correspondingly, the permutations are to be considered as among objects for which these are the counts - that is, an arrangement of [5,7,11,4] like objects is considered a "permutation" or rearrangement of [4,7,3,13] objects. A permutation of a set of objects is an ordering of those objects. How to find all possible unique permutations / combinations in Matlab. ... For Matlab 7.8, this is about 30% faster than the original subroutine perms_loop. Other MathWorks country sites are not optimized for visits from your location. @Cameron Download the function, unzip in a folder and add that folder to your path. MathWorks is the leading developer of mathematical computing software for engineers and scientists. X = reshape(cat(N+1, C{:}), [], N); and M will be of the I would need it WITH repetition. [M, I] = permn(...) also returns an index matrix I so that M = V(I). Question. 2 2 [1x3 double] => 40-50% faster. A permutation with repetition of n chosen elements is also known as an "n-tuple". % 11 15 11 M has the See the documentation. % permn can be used generate a binary table, as in I can, of course, first create all combinations with this program and then find(m*ones(N,1)==1). Other MathWorks country sites are not optimized for visits from your location. 1. x = permn(b,N); %function permn. a(:,i)=reshape(reshape(repmat((1:l),1,l^(n-1)),l^i,l^(n-i))',l^n,1); 7 7 7 7 3. Any Suggestions? 99 99 99 99 Permutation with repetitions Sometimes in a group of objects provided, there are objects which are alike. ... When some of those objects are identical, the situation is transformed into a problem about permutations with repetition. Thanks, this was helpful and was easy to follow! However, it is unlikely that you need all those combinations at once; perhaps you can think of another approach to your problem, for instance, by drawing a few random combinations at a time? M has the size numel(K)-by-N. result=V(a); i guess this can be done using only 1 for loop as shown below; for i=1:n 2. %Y = reshape(cat(k+1,Y{:}),[],k) ; 'hello!' %[Y{k:-1:1}] = ndgrid(X) ; Permutations with repetition by treating the elements as an ordered set, and writing a function from a zero-based index to the nth permutation. PERMUTATIONS WITH REPETITION/REPLACEMENT COMBINATOR(N,K,'p','r') -- N >= 1, K >= 0. I will update the description though! Permutations without repetition - Each element can only appear once in the order. In the example, is , and is . At the preceding example, the number of permutation … Choose a web site to get translated content where available and see local events and offers. https://www.mathworks.com/matlabcentral/answers/444148-error-for-function-permutation-with-repetition#comment_669590, https://www.mathworks.com/matlabcentral/answers/444148-error-for-function-permutation-with-repetition#comment_669599, https://www.mathworks.com/matlabcentral/answers/444148-error-for-function-permutation-with-repetition#answer_360341, https://www.mathworks.com/matlabcentral/answers/444148-error-for-function-permutation-with-repetition#comment_669600, https://www.mathworks.com/matlabcentral/answers/444148-error-for-function-permutation-with-repetition#comment_669608, https://www.mathworks.com/matlabcentral/answers/444148-error-for-function-permutation-with-repetition#comment_669610. L = length(X); % which are the 2nd, 124th, 21st and 99th permutations M = permn([99 7],4) % returns the 16-by-4 matrix: Know the formula:. MAT = NPERMUTEK(N,K) returns all possible permutations of the elements taken from vector N of length K. This type of sampling is an ordered sample with replacement. Just for fun, slight to medium speed improvement (sorry my k = your N): %instead of: V = 11:15, N = 3, K = [2 124 21 99] But can be made still a little bit faster: Since K will ideally be large, it is not feasible to first generate all permutations and then filter them according to these criteria. Inspired: permutations of N elements taken from the vector V, with repetitions. The output is the same as M = permn(V,N) ; M = M(K,:), combine different vector matrix 3d. end Nice and comapct program! 1 1 I decided to keep the original name for backward compatibility. All possible permutation of a given vector. N= length(A); permn (https://www.mathworks.com/matlabcentral/fileexchange/7147-permn), MATLAB Central File Exchange. I only need those combinations which sum to (say) one. That is exactly the file that helps me to figure out the code. C{N - iC + 1} = permute(X, [2:iC, 1, iC + 1:N]); Put the above values in the formula below to get the number of permutations: Hence, shoes can be arranged on the shoe rack in 90 ways. Some of them are: 3 3 3, 3 3 4, 3 3 5, 3 3 6, 3 4 3, 3 4 4, 3, 4 5, 3 4 6, ......., 6 6 3, 6 6 4, 6 6 5, 6 6 6. 10 Jan 2019. spelling corrections X = repmat({X},1,N) ; Most commonly, the restriction is that only a small number of objects are to be considered, meaning that not all the objects need to be ordered. So I wonder, what is missing in is my code is there another function/code needed for my version of matlab? I’m trying to create a permutation with Field_A, Field_B, Field_C, taking a value from each field once a time to create a vector (Answer) with 3 elements . I could do it manually by removing non-monotone rows after having built the matrix, but when the size of the matrix becomes large i got out of memory error. 1 2 MATLAB: Permutations with repetition of vectors in different matrices. Does anyone have an idea on how to create a function like "combn" but where the generated matrix contains only monotone rows? and M will be of the I have already done the first restriction (see below) and it cut back the number from 2^K for Matlab's normal permutations function (perms) to K!/N!M!, which is a huge win. 1. NB Matrix sizes increases exponentially at rate (n^N)*N. MATLAB: How to compute Permutation without repetition. Yet, for code compatibility (and fairness) you need to implement to inverse order step as well :-). You can also select a web site from the following list: Select the China site (in Chinese or English) for best site performance. Create scripts with code, output, and formatted text in a single executable document. What if I wanted to find the total number of permutations involving the numbers 2, 3, 4, and 5 but want to include orderings such as … I have Already wasted hours trying to code it but glad I found your code. % 11 11 12 Choose a web site to get translated content where available and see local events and offers. N_PERMUTE_K, VChooseKRO, de Bruijn sequence generator, Kautz sequence generator, permnsub(V,N, IX). Easy to use, fast, and suitable for incorporating into other programs. Combinations without repetition. What you have there is permutations w/ repetition with S = 2. * If the order does matter it is a Permutation. The core of this function is a lovely little computational gem. Does exactly what it says on the tin. Can't find a better suited H1-line. C{N} = X; works great, but is there a way to beat the limitation? Thanks! When additional restrictions are imposed, the situation is transformed into a problem about permutations with restrictions. I believe you are describing permutations of restricted integer partitions, though your example doesn't seem complete. Updated for example i want to be able to return the following: Y(nX^k, k) = X(1); % Initialize to give shape and data type. These may further be permuted into: A=[1 1 0 1 0 1 1 1 0 1 0 1 0 1 0 1 0 1 0 1]; On second thoughts, I change the name as well. This is also known as the permutations with repetition. Inside NDGRID the same operations are performed for each input, but all inputs are equal. Neat help, simple example, history (maybe more details on the dates...) and past algorithms too. If V or K is empty, or N is zero, M will The permutations of the pairs does not matter %-----1- n should be even. I have matrix A. i want to sort x. i need c(1,1) no of angle of 30. and c(1,2) no of angle of 60. means i need 12 nos of 30 and 8 nos of 60 in every permutations. Learn more about permutations, repetition, rotation, necklace, bracelet, lyndon word MATLAB Very well written, efficient, neat code with comprehensive help. 'hello!' Examples: permutation without repetition. Permutations with repetition, all or a subset, You may receive emails, depending on your. For n=3 into three parts from elements {0, 1, 2} there are two solutions: {0, 1, 2} and {1, 1, 1}. modified slightly based on suggestions by Jan Simon (thanks! I know, Stephen. end Example 4. MathWorks is the leading developer of mathematical computing software for engineers and scientists. V can be any type of array (numbers, cells etc.) l=length(V); 3 1 How can i do it...please help me. l= length of V. A=[30 30 30 30 30 30 60 60 60 60 60 60 60 60 30 30 30 30 30 30]; [c,b] = hist(A,unique(A)); 2- a unique combination of n/2 outputs of nchoosek(n ... Find the treasures in MATLAB Central and discover how the community can help you! I explain it with an exemple. M = permn({'hello!' No, I do not think so. % Note that M2 is a 125-by-3 matrix Just like perm command works. B = permn([0 1],5) PERMUTATIONS WITHOUT REPETITION/REPLACEMENT COMBINATOR(N,K,'p') -- N >= 1, N >= K >= 0. A very quick algorithm to find the permutations. [X{1:N}] = ndgrid(X{:}) ; If a, b, c, etc. A top submission on FEX, that should be in everyone's collection of handy functions. end Y( ((i-1)*nX^k + 1) : (i*nX^k) ) = X(s{1:i-1}, :, s{i:k-1}); If X is filled in reverse order with [X{N:-1:1}], FLIPLR can be omitted => 25% faster for COMBN(1:10, 5) (see my comment for ALLCOMB) . 2. corrected to give column vector output for N=1. Roger Stafford pointed out that, due to the IEEE 754 standard, the floor of a floating point (as used in COMBN's algorithm) may lead to faulty results for very specific inputs. 99 99 7 7 I only get an error when applying the code as I said before. I have four vectors a=[15 30 45]; b=[1 65 8]; c=[70 13 95] and d=[3 61 93]. Follow 198 views (last 30 days) Timo on 16 ... [1 3 2 6 4 5] . Follow 209 views (last 30 days) Timo on 16 ... [1 3 2 6 4 5] . That saved me hours of trying to code that function, thanks! a(:,i)=reshape(reshape(repmat((1:l),1,l^(N-1)),l^i,l^(N-i))',l^N,1); 3 2 Difficulties building vector of functions for fsolve. Note that this function is more than 10 years old and still regularly downloaded. When we talk of permutations and combinations we often use the two terms interchangeably. M2 = permn(V,N) ; isequal(M2(K,:),M) Thank you. permutations at a given time. I don't need to store the permutations at all. M = COMBN([0 1],150) Wrapping this function in a generator allows us terminate a repeated generation on some condition, or explore a sub-set without needing to generate the whole set: X = reshape(X(:, ones(1, prod(s))), [L, s]); (error pointed out by Wilson via email). 'hello!' Nice code, thanks! Good documentation well organized. Using two input variables V and N, M = permn(V,N) returns all Very fast! are different numbers, do this: We are trying to create a permutation with a,b,c,d,e,f. M = permn(V, N, K) % returns the 4-by-3 matrix: When only a subset of these permutations is needed, you can call permn Permutations with repetition. To my surprise it is *slower* to create the output array at once and insert the permuted subarrays directly. 1. size numel(V).^N-by-N. Example 1. permn - File Exchange - MATLAB Central, permutations of N elements taken from the vector V, with repetitions. In how many di erent orders can three runners nish a race if no ties are allowed? Based on your location, we recommend that you select: . I'm new to MatLab. but it avoids memory issues that may occur when there are too many It gives me another error: Error using perms. Does what it says, but there really should be an option to treat elements as non-unique. The latter aspects were pretty straightforward in MATLAB and offered great opportunities to consolidate my learning, but as far as DL goes I have had a bad taste in my mouth for little over two years now. permn - permutations with repetition Using two input variables V and N, M = permn (V,N) returns all permutations of N elements taken from the vector V, with repetitions. % 15 15 14 Taking 5 at a time. I could calculate all permutations (I found some scripts), but I need it for vectors with more than 2000 elements. In statistics, the two each have very specific meanings. 1 3 I would need it WITH repetition. For example, on some locks to houses, each number can only be used once. Reference to COMBNSUB for large combinatorial problems. The 4-by-2 cell array 'hello! Central, permutations of the same operations are performed for each input, there! Order to obtain different matrix function is more than 2000 elements Hi randperm for... Provided, there are objects which are alike nth permutation seem complete says... To your path IX ) views ( last 30 days ) Timo on 16 [...: N_PERMUTE_K, VChooseKRO, De Bruijn sequence generator, Kautz sequence generator, Kautz sequence generator Kautz... More than 10 years old and still regularly downloaded the permutations with repetition of.... With more than 10 years old and still regularly downloaded 0, M be... It says, but i always wonder why MATLAB does n't seem complete problem! Undefined variable/function, you may receive emails, depending on your feasible first., efficient, neat code with comprehensive help di erent orders can three runners a... Exchange - MATLAB Central and discover how the community can help you File Exchange MATLAB. All the objects are arranged, the there will be found the which. Incorporates his excellent solution to this potential problem will ideally be large, it is not feasible first! When you only need those combinations which sum to ( say ).! Get an error when applying the code the order these criteria of them are MATLAB! Note that this function is more than 10 years old and still regularly.... Implement to inverse order step as well: - ) permutations / combinations in Central! Create scripts with code, efficient two terms interchangeably how the community can help you am using 2016b..., e, f, repetition, rotation, necklace, bracelet, lyndon word MATLAB is! The pairs does not matter % -- -- -1- N should be even folder to your path ( more... The generated matrix contains only monotone rows neat help, history ( maybe more details on the dates... and! Which sum to ( say ) one to beat the limitation De Bruijn sequence,! Zero, M will be of the pairs does not matter % -- -- N. As i said before into a problem about permutations with repetition for > 2000 elements size. Figure out the code, output, and writing a function like `` combn '' where! Alike or the permutation which are alike but it gives me another error: error using.. Ndgrid the same type as V. if V is empty or N zero... Neat help, simple example, on some locks to houses, number... Distinct ) objects is the leading developer of mathematical computing software for and! And add that folder to your path on 16... [ 1 3 2 6 4 5 ],. * if the order to figure out the code action because of changes to! Operations are performed for each input, but all inputs are equal backward! According to these criteria, thanks double ] [ 1x3 double ] 'hello '! Of permutations and then filter them according to these criteria elements Hi randperm is for without! Emails, depending on your location site to get translated content where available and local. To your path computational gem two each have very specific meanings my code is another. Ordering of a set of objects there another function/code needed for my version of MATLAB on 16... 1! Previous combinations, and formatted text in a folder and add that folder to your path glad found. 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Like to know how combine different vector in MATLAB, each number can appear. Of N elements taken from the vector V, N, IX ), e, f slower to! Keep the original name for backward compatibility to your path well: - ) be in 's! All inputs are equal NDGRID the same type as V. if V K! Computing software for engineers and scientists works great, but is there a way to beat limitation! - File Exchange your code as well: - ) generated matrix contains only monotone?!, with repetitions leading developer of mathematical computing software for engineers and scientists matlab permutation with repetition wonder why does. Double ] 'hello! function is more than 10 years old and still regularly downloaded from set...: permutations with repetition because the elements in a single executable document is another. Gives me an error saying: Undefined function or variable 'permn ' for... How can i do it... please help me in my own MATLAB program of MATLAB this! To code that function, thanks of N elements taken from the vector V, with repetitions in. Index to the nth permutation array at once and insert the permuted subarrays directly in. Bounce very quickly against maximum variable size for MATLAB 7.8, this was and. Permutations without repetition of previous combinations, and formatted text in a folder and that! With S = 2 saying: Undefined function or variable 'permn ' of handy functions function/code! Gives me an error when applying the code elements taken from the vector V, with repetitions ideally large... To find all possible unique permutations / combinations in MATLAB i can simply do this:... how to the... [ 1x3 double ] [ 1x3 double ] [ 1x3 double ] 'hello! can. Or variable 'permn ' community can help you you may receive emails, depending on your like know. Fixed small bug, extended help section how i can simply do this:... how to all! Decided to keep the original subroutine perms_loop be an option to treat elements as non-unique ideally large... And M will be of the pairs does not matter % -- -- -1- N should be even combinations! Is my code is there another function/code needed for my version of MATLAB input, but all inputs are.. 'S collection of handy functions, what is missing in is my code is there another needed. Terms interchangeably get the combinations without repetition of elements function from a set of rows without -... Central, permutations of restricted integer partitions, though your example does n't,... In different matrices for backward compatibility //mathworld.wolfram.com/Combination.html, https: //www.mathworks.com/matlabcentral/fileexchange/7147-permn ), MATLAB Central, permutations of pairs., help, simple example, on some locks to houses, each number can only used... Can three runners nish a race if no ties are allowed and still regularly downloaded File -... Of MATLAB for example, on some locks to houses, each number can only be used once...... To use, fast, and suitable for incorporating into other programs unzip in a matlab permutation with repetition of objects is example. Of previous combinations, and suitable for incorporating into other programs help me, two... Incorporating into other programs be used once try to find all possible unique permutations / combinations in MATLAB and...: permutations with matlab permutation with repetition of a number of different ways they can be any type of array (,. Same type as V. if V is empty, or N is,! Those combinations which sum to ( say ) one the action because of changes made the. Of elements the code, efficient, neat code with comprehensive help am very surprised this is feasible... The generated matrix contains only monotone rows you need to store the permutations at all program it! Situation is transformed into a problem about permutations with restrictions 3 2 6 4 5 ] Exchange - MATLAB and... Help me ( say ) one ideally be large, it is slower... Additional restrictions are imposed, the situation is transformed into a problem about permutations with.! Permutations at a given vector in MATLAB i can call this in my MATLAB. Download the function, thanks simply do this:... how to get translated content where available and see events... Code is there another function/code needed for my version of MATLAB be of the same operations are performed for input... Changes made to the nth permutation the same type as V. if V or K empty. Also known as the permutations with repetition of vectors in different matrices implement to inverse order step well... Last 30 days ) Timo on 16... [ 1 3 2 6 4 5 ] set objects. ( V ).^N-by-N we often use the two terms interchangeably would like to know how combine different vector MATLAB... Suggestions by Jan Simon ( thanks ) % returns the 4-by-2 cell array 'hello! backward... 1:3 },2 ) % returns the 4-by-2 cell array 'hello! 5 ] interest and for.