Possible issue in the calculation of the average branch length.

[GabrieleZucca]

Dear AnalyzeSkeleton developers,

I'm using the latest Fiji release (based on ImageJ 1.51w) on Ubuntu 16.04. The Java version is 1.8.0_171.
I noticed that sometimes the "Average Branch Length" value in is different from the mean of the branch lengths contained in the "Branch information" file.

For example, when processing this image

I obtain the following CSV files:

Branch_information_Batch_aec+af+novegf_merged4.txt

Results_Batch_aec+af+novegf_merged4.txt

At row 6 in the "Results" file, the "Average Brench Length" value is 19.624, while the average of the individual branch lengths, obtained from the "Branch information" file, is 20.478.

Thanks for your useful plugin!