Call elements for a cell array

83 次查看（过去 30 天）
Nikolas Spiliopoulos
编辑： Nut 2017-1-20
Hi there,
I am a beginner so the question maybe will be silly for you:
I have an cell 3x1 , where each element is an array
how can I select the first element, do some calculations and then the second one? (and so on..)
its a for loop but i cant find the proper syntax. thanks
Nikolas
  4 个评论
显示 2更早的评论
Nikolas Spiliopoulos
Nikolas Spiliopoulos 2017-1-20
i tried it, but I get an output like this = [1X24];[1X24];[1x24];
Stephen23
Stephen23 2017-1-20
编辑：Stephen23 2017-1-20
@Nikolas Spiliopoulos: That is a cell array containing all of your results.
What do you imagine should happen? What do you think MATLAB should do?
You stored the results in a cell array, and there they are, in a cell array. Exactly where you put them. My comments already showed you how to look at the values inside that cell array, if you want to do so.
Now that all of your results are stored in one cell array you could easily:
  • combine the separate numeric arrays into one numeric array.
  • loop over that output cell array and do further work: e.g. save the data, etc.
  • pass that cell array to other operations or functions.
  • etc
What happens next depends on your workflow. Which do you want to do?

请先登录，再进行评论。

请先登录，再回答此问题。

采纳的回答

Stephen23
Stephen23 2017-1-20
编辑：Stephen23 2017-1-20
C = {0:3, 4:5, 6:9};
out = NaN(size(C));
for k = 1:numel(C)
out(k) = mean(C{k});
end
or if the outputs are non-scalar, then put in a cell array:
out = cell(size(C));
for k = 1:numel(C)
out{k} = mean(C{k});
end
https://www.mathworks.com/help/matlab/matlab_prog/access-data-in-a-cell-array.html
  7 个评论
显示 5更早的评论
Stephen23
Stephen23 2017-1-20
@Nikolas Spiliopoulos: remember to accept the answer that helps you most.

请先登录，再进行评论。

更多回答（2 个）

Niels
Niels 2017-1-20
编辑：Niels 2017-1-20
Hi,
with {n} you get access to the nth element
>> a={[1 2] , 'abcdefg', randn(4)}
a =
1×3 cell array
[1×2 double] 'abcdefg' [4×4 double]
>> a{1}
ans =
1 2
or in a loop:
for i=1:3
b=a{i}; % you dont need to declare a new variable
% you can also work with a{i}
>> a{3}(1:2,2:3)
ans =
0.3188 3.5784
-1.3077 2.7694
end
this documentation might help you as well:
Access Data in a Cell Array
Nut
Nut 2017-1-20
编辑：Nut 2017-1-20
Hi,
I think the following example could be a basic help, is it useful for you?
% 3x1 cell building (example)
cellarray{1} = [1 2 3];
cellarray{2} = [4 5 6];
cellarray{3} = [7 8 9];
cellarray = cellarray';
% Get the second array
cellarray{2}
% Get the first element of the third array
cellarray{3}(1)
% Get the first cell element
cellarray(1)
  2 个评论
Nikolas Spiliopoulos
Nikolas Spiliopoulos 2017-1-20
yeah its ok, however how can I use the for loop with that in order to choose one element(array) a time? thanks
Nut
Nut 2017-1-20
编辑：Nut 2017-1-20
I'm thinking to something like:
for i = 1:numel(cellarray)
array = cellarray{i};
% Do your calculations using "array"
end

请先登录，再进行评论。

类别

在 Help Center 和 File Exchange 中查找有关 NaNs 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