Im going to explain what I need to do.
First I would like to open 400 files e.g ISO1.dat,..ISO400.dat, within this files I have datas which means numbers for instance( X,Y,Z are vectors)
ISO1.dat has X1,Y1,Z1 vectors
ISO2.dat has X1,Y2,Z2 vectors
ISO3.dat has X1,Y3,Z3 vectors
I only need...