It is a warning, not an error. In this FCS file, there is one letter 'F' preceded with spaces at the end of TEXT segment without any value pared with. So it is simply ignored and fcs file is probably parsed ok. Mike On 07/30/2014 09:03 AM, John Li wrote: > Hi Mike, > > I'm trying to parse a FCS file from here. > > http://www.c2b2.columbia.edu/danapeerlab/html/CYT/data/wanderlust/Be ndall%20et%20al%20Cell%20Sample%20A_basal.fcs > > I get the following error. But I'm not sure what caused the error. > Would you please let me know how to correctly parse this file? Thanks. > >> f=read.FCS('A_basal.fcs') > Warning messages: > 1: In fcs_text_parse(txt, emptyValue = emptyValue) : > keyword: > F is dropped because no value found! > 2: In fcs_text_parse(txt, emptyValue = emptyValue) : > keyword: > F is dropped because no value found! > 3: In readBin(con = con, what = dattype, n = count, size = size, > signed = signed, : > 'signed = FALSE' is only valid for integers of sizes 1 and 2 >