Thanks all...Reduce() is the new function I learnt today... Thanks... BR, Shubha Shubha Karanth | Amba Research Ph +91 80 3980 8031 | Mob +91 94 4886 4510 Bangalore * Colombo * London * New York * San José * Singapore * www.ambaresearch.com -----Original Message----- From: Barry Rowlingson [mailto:[EMAIL PROTECTED] Sent: Wednesday, June 04, 2008 8:49 PM To: Shubha Vishwanath Karanth Cc: [EMAIL PROTECTED] Subject: Re: [R] sum of unknown number of matrices
Shubha Vishwanath Karanth wrote: > I need: > >> a+b+c+d > > [,1] [,2] > > [1,] 4 12 > > [2,] 8 16 > > > > Something like do.call("+",l) is not working...why is this? Because do.call constructs a function call with the elements of l as arguments, so you end up with: "+"(1:4, 1:4, 1:4, 1:4) but "+" only takes two arguments. Use 'Reduce': > Reduce("+",l) [,1] [,2] [1,] 4 12 [2,] 8 16 Barry This e-mail may contain confidential and/or privileged i...{{dropped:10}} ______________________________________________ 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.