How to avoid having duplicate index result?

조회 수: 3 (최근 30일)
Hardi Mohammed
Hardi Mohammed 2019년 2월 21일
댓글: Hardi Mohammed 2019년 2월 25일
I have written this code it works correct but one thing is that when I run it it gives me duplicate result how can I avoid repetion if I run it for 24 times.
x=zeros(4,4);
temp=0;
test=zeros(3,3);
b=sum(x,1);
r=randperm(4);
for i=1:4
temp=0;
for j=1:4
% r=randi([1,3]);
if temp~=r(j)
temp=r(j);
if sum(x(i,:))==0 && b(temp)==0
x(i,temp)=1;
end
end
end
b=sum(x,1);
end
x
  댓글 수: 3
Stephen23
Stephen23 2019년 2월 21일
편집: Stephen23 2019년 2월 21일
Original (better explained) question, with simple three line answer:
@Hardi Mohammed: why do refuse to use perms, which is the best way to generate those 6/24/... permutations that you request. Please explain why perms does not work for you.
Hardi Mohammed
Hardi Mohammed 2019년 2월 25일
@Stephen Cobeldick
it works well but I have problem when I change the size of matrix for 2 row 3 column
then it does not give all the possiblites

댓글을 달려면 로그인하십시오.

답변 (2개)

Jan
Jan 2019년 2월 21일
If I assume, that this code satisfies your needs for 1 call:
x = zeros(4, 4);
x(sub2ind(size(x), 1:4, randperm(4,4))) = 1;
I assume, that this creates all wanted results:
order = perms(1:4);
n = size(order, 1);
order = order(randperm(n, n), :); % If a random order is wanted
x = zeros(4, 4, n);
for k = 1:n
index = sub2ind([4, 4, n], 1:4, order(k, :), repmat(k, 1, 4));
x(index) = 1;
end
Now x(:, :, k) is the wanted submatrix.
  댓글 수: 2
Jos (10584)
Jos (10584) 2019년 2월 21일
you can leave out the sub2ind ...
x = eye(4) ;
x = x(randperm(4),:)
Jan
Jan 2019년 2월 21일
편집: Jan 2019년 2월 21일
@Jos: Your are correct, but the sub2ind method is not needed for the random permutation, but for the construction of all 24 different matrices.

댓글을 달려면 로그인하십시오.


Jos (10584)
Jos (10584) 2019년 2월 21일
편집: Jos (10584) 2019년 2월 21일
This also produces the N! possibilities. No loop, no sub2ind, only the outcome of perms as column indices ...
N = 4
X = eye(N) ;
X = reshape(X(:, perms(1:N).'), N, N, [])

카테고리

Help CenterFile Exchange에서 Creating and Concatenating Matrices에 대해 자세히 알아보기

Community Treasure Hunt

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

Start Hunting!

Translated by