Radek,I believe the tool Base Coverage under Operate on Genomic Intervals (bx) is what you are looking for. It simply outputs the total number of bases covered by a set of intervals, which is the combined length of all intervals.In addition, multiplying the mean by the number of regions would count the bases covered by overlapping regions twice (or more).Perhaps adding "Total" to the summary stats is a good idea though.IanRadek Szklarczyk wrote:hi!i found it hard to get the sum of the length of regions. I ended up multiplying mean (sum stats) by the number of regions, for which I had to calculate the length with an expression first. Maybe I overlooked a simple way of getting what i want?radek---Radek Szklarczyk, radek@cs.vu.nl, www.cs.vu.nl/~radek <http://www.cs.vu.nl/%7Eradek>------------------------------------------------------------------------_______________________________________________Galaxy-user mailing list