How to compile the average values of a variable in .mat files

Question

Paul Torres 2018-7-23

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/411761-how-to-compile-the-average-values-of-a-variable-in-mat-files

编辑： Adam Danz 2018-7-24

I have 81 .mat files that correspond to the years 1930 to 2010 and each contain a variable named 'zdaily'. In each zdaily, there are is a matrix that is 240x121x366or365 depending on if that year was a leap year or not. I'm trying to create a 'for loop' that will not only compile the .mat files into one large matrix but also take the average over the time dimension so that instead of 81x365or366, it will just be 81. Thanks

2 个评论
显示无隐藏无

Giridharan Kumaravelu 2018-7-23

编辑：Giridharan Kumaravelu 2018-7-23

在 MATLAB Online 中打开

average = zeros(81,1); 
for i = 1:81
      data = matfile("filenameOfyear1930+i.mat");
      average(i) = mean(data.zdaily,3);
end

Is this what you wanted?

Paul Torres 2018-7-24

This would be close but does it account for leap years?

请先登录，再进行评论。

请先登录，再回答此问题。

Answer 1

Adam Danz 2018-7-23

0
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/411761-how-to-compile-the-average-values-of-a-variable-in-mat-files#answer_330000

编辑：Adam Danz 2018-7-23

在 MATLAB Online 中打开

Let's say your mat file is called 'myMatFile.mat' and the variable of interest is 'zdaily'.

% Pull data from file
filename = 'C:\Users\me\Documents\MATLAB\myMatFile.mat'; 
data = matfile(filename); 
zdaily = data.zdaily; 
% Average over the 2nd dim
m = mean(zdaily ,2); 
% Check size 
size(m) %should be [1,81]

The same thing with less lines of code (faster & cleaner)

data = matfile('C:\Users\me\Documents\MATLAB\myMatFile.mat'); 
m = mean(matfile.zdaily,2);

2 个评论
显示无隐藏无

Paul Torres 2018-7-24

There are 81 different .mat files, this code would only work for one, right?

Adam Danz 2018-7-24

编辑：Adam Danz 2018-7-24

Yes, you'd need to implement a loop as Giridharan demonstrated in the comments section above. For example, you could create a cell array of all your filenames and loop through each element of the cell array.

请先登录，再进行评论。