I have this code, where 'data' changes its size with every loop and has to be divided into four equal segments. This division has to be stored in variable 'epoch'. storing it in cell variable isn't an option. How can I store differen lengths of data?

1 次查看（过去 30 天）
Bubblesjinx
Bubblesjinx 2018-12-4
评论： Guillaume 2018-12-4
data = y;
seg = y/4;
signal = data(1,:);
for e = 1:4
epoch (e,:) = signal(1+(e-1)*seg:e*seg);
end

请先登录，再回答此问题。

采纳的回答

Guillaume
Guillaume 2018-12-4
epoch = reshape(signal, [], 4).'
No need for a loop.
  6 个评论
显示 4更早的评论
Bubblesjinx
Bubblesjinx 2018-12-4
Thanks for stating all the possible options. For my requirement, I would go for "splitting into four equal parts using a cell array", for which I have tried following:
epochs{1} = e;
epochs{2} = signal(1+(e-1)*seg:e*seg);
Then I have following error:
Unable to perform assignment because brace indexing is not supported for variables of this type.
Guillaume
Guillaume 2018-12-4
You get this error because you're reusing epoch that you previously created as a double array. You would have avoided this problem if you had preallocated epoch before the loop. It's always a good to preallocate arrays that you're assigning to in a loop. It makes the loop faster, and avoids this type of errors:
epoch = cell(1, 4); %preallocate epoch
for .... your loop as normal
As usual for matlab, there's no need for the loop (and the preallocation):
defaultlength = ceil(numel(signal) / 4);
epoch = mat2cell(signal, 1, [ones(1, 3) * defaultlength, defaultlength + mod(defaultlength, -4)])
The last element of epoch will be up to 3 elements shorter than the previous 3.

请先登录，再进行评论。

更多回答（0 个）

类别

在 Help Center 和 File Exchange 中查找有关 Correlation and Convolution 的更多信息

标签

Community Treasure Hunt

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

Start Hunting!

Translated by