Hi Stefan, you could try something like,
x <- c(2,4,7) as.numeric(!is.na(match(seq(1, max(x)), x))) I hope this helps. Best, Dimitris ---- Dimitris Rizopoulos Doctoral Student Biostatistical Centre School of Public Health Catholic University of Leuven Address: Kapucijnenvoer 35, Leuven, Belgium Tel: +32/16/396887 Fax: +32/16/337015 Web: http://www.med.kuleuven.ac.be/biostat/ http://www.student.kuleuven.ac.be/~m0390867/dimitris.htm ----- Original Message ----- From: "Stefan Böhringer" <[EMAIL PROTECTED]> To: "R Help" <[EMAIL PROTECTED]> Sent: Monday, July 26, 2004 10:45 AM Subject: [R] computing sum of indicator variables > My problem is as follows: > i is a list of integers of variable length. Now I want to compute a new > vector/array that contains 1's at the positions indicated in i. For > example: > c(2, 4) -> c(0, 1, 0, 1) > > Using something like > i = i - c(0, i[2:length(i) - 1]); > sapply(i, function(x) c(rep(0, x - 1), 1))); > > faces me with the problem of concatenating the result, which I could > somehow not find a solution for. > > Thank you very much in advance. > > Stefan > > ______________________________________________ > [EMAIL PROTECTED] mailing list > https://www.stat.math.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html ______________________________________________ [EMAIL PROTECTED] mailing list https://www.stat.math.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html