- Generate the vectors - I'll call them b - in your for-loop and keep track of the longest vector that is generated in the loop. Store the vectors as a matrix: b(:,ii).
- Once done, initialize a 0-matrix A using zeros(M,N) where M is equal to the size of the longest vector and N is the total number of vectors.
- Lastly run another for-loop to paste into the matrix the individual vectors using something like:
How to combine random size arrays in one matrix - in a loop?
3 visualizaciones (últimos 30 días)
Mostrar comentarios más antiguos
Jeroen
el 15 de En. de 2014
Hey, I've been able to find a lot of solutions for my matlab program on this site but the next problem still goes unanswered.
I have a loop in which every run a vector is created with a random size. After the loop is finished I want all these vectors presented in a matrix with each vector as a column. How can I do this? The shorter vectors may either be filled with NaN's or zero's.
In essence the program looks like this:
for i=1:1:10;
l=ceil(rand(1)*10);
vector=rand(l,1);
end
matrix=[vector1 vector2 ... vector10 ];
Thanks in advance for helping me out.
0 comentarios
Respuesta aceptada
Mischa Kim
el 15 de En. de 2014
Editada: Mischa Kim
el 15 de En. de 2014
Hello Jeroen,
A(:,ii) = [b(:,ii); zeros(length(A(1,:)) - length(b(:,ii)),1)]
where ii is the running index of the loop.
You can also get this done using only one loop, of course, by simply concatenating vectors that have been "filled up" with the adequate number of 0s, or filling up the existing matrix before concatenating.
2 comentarios
Mischa Kim
el 16 de En. de 2014
Run the code below. Not optimized but it does what you are looking for:
A = [0];
for ii = 1:10
b = ones(randi([1,10],1,1), 1); % here you put your random-sized vector
if (size(A(:,1)) == 1)
A = b;
else
if (length(b) < length(A(:,1)))
A = [A [b; zeros(length(A(:,1)) - length(b),1)]];
end
if (length(b) == length(A(:,1)))
A = [A b];
end
if (length(b) > length(A(:,1)))
A = [[A; zeros(length(b) - length(A(:,1)), length(A(1,:)))] b];
end
end
end
display(A);
Venkat Ta
el 3 de Mayo de 2018
it works in between the program but this whole code does not work if I created as function
Más respuestas (3)
Jos (10584)
el 16 de En. de 2014
Editada: Jos (10584)
el 16 de En. de 2014
You have several options how to store vectors with different lengths.
1) use cell arrays
C = cell(k,1) ;
for k=1:10,
L = ceil(10*rand) ;
C{k} = rand(L,1) ;
end
2) subsequently you can concatenate these cells into a single array, in which shorter vectors are padded with a chosen value. I have submitted the function PADCAT to the file exchange, which makes this a trivial conversion:
[M, tf] = padcat(C{:}) % pad with NaNs by default
M(~tf) = 0 % change NaNs to zeros
0 comentarios
Amit
el 16 de En. de 2014
how about:
matrix = zeros(10,10);
flag = 1;
for i = 1:10
m = randi(10);
matrix(1:m,flag:flag+m-1) = rand(m);
flag = flag + m;
end
0 comentarios
Andrei Bobrov
el 16 de En. de 2014
for jj = 1:10
v = randi(randi(234),randi(12),1);
if jj==1
out = v;
else
n = [size(out,1),numel(v)];
out(n(1)+1:n(2),1:jj-1) = nan;
out(1:max(n),jj) = nan;
out(1:n(2),jj) = v;
end
end
2 comentarios
Ver también
Categorías
Más información sobre Loops and Conditional Statements en Help Center y File Exchange.
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!