how to keep first 3 datas and obtain average, then skip or ignore the next 3 data and keep next 3 datas again....??

Question

Eder Hernandez Martinez 2020-2-23

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/507058-how-to-keep-first-3-datas-and-obtain-average-then-skip-or-ignore-the-next-3-data-and-keep-next-3-da

评论： Eder Hernandez Martinez 2020-2-23

Hi all.

I have a 216 data in a one column from excel. but i want to keep first 3 datas and obtain average, then skip or ignore the next 3 data and keep next 3 datas again until finish 1:216, someone how to do that?

0 个评论
显示 -2更早的评论隐藏 -2更早的评论

请先登录，再进行评论。

请先登录，再回答此问题。

Answer 1

Thiago Henrique Gomes Lobato 2020-2-23

0
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/507058-how-to-keep-first-3-datas-and-obtain-average-then-skip-or-ignore-the-next-3-data-and-keep-next-3-da#answer_416926

在 MATLAB Online 中打开

An efficient way to do this is to create all the index that are going to belong to the average and then do it in a vectorized way. In your case, you can define each value belonging to the average with intervals of 6 values, an example can be done like this:

N = 15;
A = 1:N; % Simple vector to verify result, substitute by your A with N = 216
idx1 = 1:6:N;
idx2 = 2:6:N;
idx3 = 3:6:N;
Average = mean( [A(idx1);A(idx2);A(idx3)] )'
Average =
     2
     8
    14

3 个评论
显示 1更早的评论隐藏 1更早的评论

Thiago Henrique Gomes Lobato 2020-2-23

在 MATLAB Online 中打开

You use the same logic as my answer, in your exact case you can write

v1=dat(5:end,9);
N = size(v1,1);
idx1 = 1:6:N;
idx2 = 2:6:N;
idx3 = 3:6:N;
filteredv1=[v1(idx1),v1(idx2),v1(idx3)]';
filteredv1 = filteredv1(1:end)';
Averagev1 = mean( [v1(idx1),v1(idx2),v1(idx3)],2 );