how to split a vector into small subvectors based on condition

조회 수: 10 (최근 30일)
Elysi Cochin
Elysi Cochin 2020년 3월 15일
댓글: Ameer Hamza 2020년 3월 15일
how can i split a vector into smaller sub vectors, such that the sum of each vectors is less than N
N = 60
V = [30 35 24 15 14 48];
  댓글 수: 3
Elysi Cochin
Elysi Cochin 2020년 3월 15일
very sorry, question edited, should not be greater was my question
Walter Roberson
Walter Roberson 2020년 3월 15일
Breaking up into individual elements satisfies the stated conditions. There are other solutions too, but the question does not prevent the algorithm from being lazy and not even trying a different solution.

댓글을 달려면 로그인하십시오.

채택된 답변

Ameer Hamza
Ameer Hamza 2020년 3월 15일
편집: Ameer Hamza 2020년 3월 15일
From your other question: https://www.mathworks.com/matlabcentral/answers/510716-compute-from-a-set-of-parameters. I suspect that you want to find all distinct combination of elements where the sum is less than 60 while keeping the number of trips to a minimum. The following code will find an optimal solution; however, it will only work if the number of elements of V is small (say less than 20). The solution have exponential time and space complexity, so the required resources will grow very quickly. For large number of variables, I would recommend using some greedy method, which can give a sub-optimal solution.
N = 60;
V = [30 35 24 15 14 48];
a = mat2cell(repmat([0 1], numel(V), 1), ones(size(V)), 2);
combs = logical(combvec(a{:})'); % create all possible combinations
combs(1, :) = []; % remove a trivial combination
cost = sum(combs.*V, 2);
valid_index = cost < N;
valid_combs = combs(valid_index, :);
valid_costs = cost(valid_index);
[valid_costs, index] = sort(valid_costs, 'descend');
valid_combs = valid_combs(index, :);
optimal_combs = logical([]);
while ~isempty(valid_combs)
current_comb = valid_combs(1,:);
optimal_combs = [optimal_combs; current_comb];
index = any(valid_combs(:, current_comb) == valid_combs(1, current_comb), 2);
valid_combs(index, :) = [];
end
result = {};
for i=1:size(optimal_combs,1)
result{i} = V(optimal_combs(i,:));
end
  댓글 수: 6
Elysi Cochin
Elysi Cochin 2020년 3월 15일
sorry sir for the confusion, now only saw the names were different
Thank you sir for your answers
Ameer Hamza
Ameer Hamza 2020년 3월 15일
No problem. Gald to be of help.

댓글을 달려면 로그인하십시오.

추가 답변 (1개)

Ahmed Anas
Ahmed Anas 2020년 3월 15일
편집: Ahmed Anas 2020년 3월 15일
Dear, it will give you the desired results
clear all
clc
V = [30 35 24 15 14 48]
N=60
for i=1:size(V,2)
subsA = nchoosek(V,i);
for j=1:size(subsA)
Sum=sum(subsA(j,:));
if Sum<N
G=subsA(j,:)
end
end
end
  댓글 수: 3
Walter Roberson
Walter Roberson 2020년 3월 15일
I suspect that the sub-vectors are intended to be consecutive elements.
Elysi Cochin
Elysi Cochin 2020년 3월 15일
sir, i executed the code, its somewhat close,
i dont want repeatition of elements, once if i store a value into a new subvector , then i wont consider that value
my expected output is
{ [ 30 15 14] [ 35 24 ] [ 48] }

댓글을 달려면 로그인하십시오.

카테고리

Help CenterFile Exchange에서 Numeric Types에 대해 자세히 알아보기

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by