After some processing... ct.df <- data.frame(time,conc) ct.df gives time conc 1 0 164.495456 2 1 133.671185 3 2 108.622975 4 3 88.268468 5 4 71.728126 6 5 58.287225 7 6 47.364971 8 7 38.489403 9 8 31.276998 10 9 25.416103 11 10 20.653462 12 11 16.783276 13 12 13.638313 14 13 11.082674 15 14 9.005927 16 15 7.318336
- Ignored: 17 16 5.946977 18 17 4.832592 19 18 3.927028 20 19 3.191155 21 20 2.593175 22 21 2.107248 23 22 1.712378 24 23 1.391501 25 24 1.130752 I need to find the time when conc < 25. I can read it off the table but I am looking for a programmatic solution. Thanks. Oscar -- Oscar A. Linares, MD Clinical Assistant Professor of Medicine Department of Medicine University of Toledo College of Medicine Toledo, Ohio 43606-3390 Attending Physician The Detroit Medical Center (DMC) Harper University Hospital Wayne State University School of Medicine Detroit, Michigan 48201 Director Translational Pharmacokinetics & Pharmacogenomics Unit, La Plaisance Bay, Bolles Harbor, MI Medical Director Monroe Pain Center Monroe, MI 48162 (http:www.monroepaincenter.com) Phone (734) 240-8400 Cell (734) 637-7997 Fax (734) 243-6254 oalinare...@gmail.com [[alternative HTML version deleted]] ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.