How to loop around cumsum ?

2 次查看（过去 30 天）
Lea Enguehard
Lea Enguehard 2020-6-3
评论： Image Analyst 2020-6-4
Hello,
I have a file 3600x601 and I would like to obtain a file 1x601 where each 601 value in the new file is the cumulative sum of the associated 3600 values.
I have written this:
for i =1:601
Csflux = cumsum(Flux(i,:));
end
where Flux is 3600x601
At the end I have Csflux 1x601 but it's the cumulative sum of each 601, so it's not what I want.
Do you have any ideas?
I am working on a current fluxes in a coral reef :)
  1 个评论
James Tursa
James Tursa 2020-6-3
编辑：James Tursa 2020-6-3
Please show a small example. E.g., show a specific 5x3 input and the desired output.

请先登录，再进行评论。

请先登录，再回答此问题。

回答（1 个）

Image Analyst
Image Analyst 2020-6-3
Did you just want the sum of each column? Like this:
columnSums = sum(Flux, 1);
  2 个评论
Lea Enguehard
Lea Enguehard 2020-6-3
I want the cumulative sum of each 3600 value
Image Analyst
Image Analyst 2020-6-4
Lea, we still don't know what you mean, in spite of James and I asking for more clarification or an example. By the way, is this homework?
Is this what you mean?
% Create small test data set.
Flux = randi(9, 5, 15);
columnSums = sum(Flux, 1);
cSums = zeros(size(Flux)); % Preallocate space.
for column = 1 : size(Flux, 2)
thisCumulativeSum = cumsum(Flux(:, column)) % Let's see it first (optional).
cSums(:, column) = thisCumulativeSum
end
Here each column is the cumulative sum, as you go down the rows, of the original column in Flux.

请先登录，再进行评论。

类别

在 Help Center 和 File Exchange 中查找有关 Loops and Conditional Statements 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