Problem with the mean function

3 次查看（过去 30 天）
Alexandre
Alexandre 2012-5-2
Hi everyone,
I've got a little pb with the 'mean' function :
My matrix has a class 'double' on my workspace : &lt70080*1 double> I would like to do an average of those values :
moyenne = mean(refoulement(1:8760,1)) and the answer is NaN. The values are positives.
Do you have an idea ?
Thanks !

请先登录，再回答此问题。

采纳的回答

Kye Taylor
Kye Taylor 2012-5-2
Try this
meanWithoutNans = mean(refoulement(~isnan(refoulement)));
  2 个评论
Alexandre
Alexandre 2012-5-2
Ok it works perfectly. If i want to select some rows in my matrix, where should I put it ?
Here for ex : meanWithoutNans = mean(refoulement(~isnan(refoulement(1:i,:)))); ?
Ty
Kye Taylor
Kye Taylor 2012-5-2
I interpret you question as, "How do I take the mean of rows in a matrix and avoid the nans?"
To do that, try
meanOfRowsWithoutNans = zeros(size(refoulement,1),1);
for i = 1:size(refoulement,1) % for each row
meanOfRowsWithoutNans(i) = ...
mean(refoulement(i,~isnan(refoulement(i,:))));
end

请先登录，再进行评论。

更多回答（3 个）

Image Analyst
Image Analyst 2012-5-2
What does this say:
hasNans = max(isnan(refoulement))
I want to see if there are any nan's in your original matrix.
Sean de Wolski
Sean de Wolski 2012-5-2
If you have the Stats Toolbox, take a peak at:
doc nanmean
Also this FEX submission:
http://www.mathworks.com/matlabcentral/fileexchange/6837-nan-suite
Alexandre
Alexandre 2012-5-2
The answer for hasNans = max(isnan(refoulement)) is one thus I guess there are some NaN in the column.
What should I do then ?
I saw some topic explaining that in that case I have to code a function to get rid of the NaN, is that correct ?
Unfortunately, I don't have that toolbox.
Thanks for your help !

类别

在 Help Center 和 File Exchange 中查找有关 Logical 的更多信息

标签

产品

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by