Why do i get NaN?

Dear all,

i try to run this very simpel Code (it worked already with other Input files with identical build-up). I try to import a table with 2 columns from 6 .csv files each and want to declare a starting point in column 1 for every table with "anfang" to average all values from column 2 from the starting point to end. As i said it works with other .csv files but in this case i only get an average value for the first 2 files. For the other 4 files i get "NaN". I tried to debug the code but i dont get any errors at this point and i also checked the columns of the imported tables but everything seems good (no critical values that could affect mathematical operations or something else). I also tried to change the values in "anfang" to try a earlier or later starting point but its also didn't work.

Thanks for help

clear all
close all

%%
filename = dir('*.csv');
%% avgT
    anfang = [700,700,200,100,140,140];

%%
for idx1 = 1:length(filename)
    
    Cell{idx1} = readtable(filename(idx1).name);
    Cell{idx1} = table2array(Cell{idx1});
  
    
  avgT (idx1) = mean(Cell{idx1}(anfang:end,2))


end

[KSSV]

Try using nanmean instead of mean.

[Tim K]

I could solve this problem with some help in an other way but thank you for your time!

Answer 1

[Scott MacKenzie]

It's hard to say without being able to run your code, but it seems to me that anfang in

avgT(idx1) = mean(Cell{idx1}(anfang:end,2));

should include an index. Try

avgT(idx1) = mean(Cell{idx1}(anfang(idx1):end,2));

Also, why are you putting the data from the files into a cell array of cell arrays? The lines in your for-loop can be simplified. Try

    T = readtable(filename(idx1).name);
    C = table2array(T);    
    avgT(idx1) = mean(C(anfang(idx1):end,2));

[Tim K]

Thank you very much! Inlcude the index at "anfang" worked well. And also thank you for simplifications!