Hi, I have a set of experiments showing a bimodal behaviour and would like to draw a cumulative relative frequency curve(ogive). I would also like to read off my lower limit a the 2.5% point and the upper at 97.5% in oredr to have a 5% sig level. Does anyone know if there is a function around that can perform either of these operations. I also know that the stepfun library has got the ecdf function which probably only needs a few modifications to make the ogive(?) Thank you in advance, Fergus