MATLAB: Can we sum a series of values,even some of them are “Inf”?If i want to do it,how can i do

MATLABmeansum

I get a series answer of optimal problem in several times,and i want to sum of them and average them,however, some of them are "Inf",can i or how to write a code to ignore those "Inf" and sum the others which is not "Inf" ?
Also,if i can sum them when some of them are "Inf",and don't know the amount of value which is "Inf",do we have some method to average them,i mean,ignore the "Inf" and average the others?
The version of matlab is 2015a

Best Answer

No. You cannot add numbers if some of them are infs, at least not without getting an inf as a result. OR you might even get a NaN, since inf+ -inf will result in a NaN.
sum([1:5,inf,6,7,-inf])
ans =
   NaN
but
sum([1:5,inf,6,7,inf])
ans =
   Inf
You also cannot know that some infs are bigger than other infs, as I think you may have asked.
If you want to form a sum of numbers, excluding infs, this is trivial:
V = [1:5,inf,6,7,-inf];
sum(V(~isinf(V)))
ans =
    28
Also, if you have a reasonably recent MATLAB release, you will find that tools like mean allow you to ignore NaNs in the data as an option. So you could simply convert all infs into NaNs, then use mean with the correct option set. (Or use nanmean in older releases.)
Related Question