Find the threshold point in a matrix
2 visualizzazioni (ultimi 30 giorni)
Mostra commenti meno recenti
I have a 178x13 double matrix. In each column there is a point where each data value starts to stay same. I want to find them (row number). For example for the first column it is 70. I tried "find(diff(values(:,1)) == 0, 1, 'first')" but it is not working. How can I do this? Thanks for the help.
![](https://www.mathworks.com/matlabcentral/answers/uploaded_files/170022/image.png)
0 Commenti
Risposta accettata
Image Analyst
il 22 Nov 2017
You can have differences equal to zero that are not in the last stretch of zeros. Therefore you need to use findgroups() or regionprops() to find the first element of the last group of zeros. If you need a demo, attach your data in an mat file with the paper clip icon.
3 Commenti
Image Analyst
il 23 Nov 2017
That's not a great example because all those columns go steady state at exactly the same row. This simple code will do it quickly:
data = importdata('myfile.txt')
[rows, columns] = size(data)
for col = 1 : columns
fprintf('Finding where column #%d equals %f . . . ', col, data(end, col));
steadyStateLocations(col) = find(data(:, col) ~= data(end, col), 1, 'last');
fprintf('it happens at row %d.\n', steadyStateLocations(col));
end
Più risposte (0)
Vedere anche
Categorie
Scopri di più su String Parsing in Help Center e File Exchange
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!