On Wed, 5 Sep 2007, Greg Snow wrote: >> ?mapply >> mapply('+', a, b, SIMPLIFY=FALSE) >> colSums(mapply('+', a, b))
or sapply( a, sum ) + b * sapply( a, length ) or even sapply( a, sum ) + b * 2 if all list components in 'a' are of length 2. Then there are the do.call( cbind , a ) incantations. Chuck > > Hope this helps, > > -- > Gregory (Greg) L. Snow Ph.D. > Statistical Data Center > Intermountain Healthcare > [EMAIL PROTECTED] > (801) 408-8111 > > > >> -----Original Message----- >> From: [EMAIL PROTECTED] >> [mailto:[EMAIL PROTECTED] On Behalf Of Yongwan Chun >> Sent: Monday, September 03, 2007 12:36 AM >> To: r-help@stat.math.ethz.ch >> Subject: [R] element wise opertation between a vector and a list >> >> I want to try to get a result of element wise addition >> between a vector and a list. It can be done with "for >> statement." In order to reducing computing time, I have tried >> to avoid "for state." If anybody give me an idea, I would >> apprecite it much. >> >> for example, with a & b as below lines, >> >> a<- list(c(1,3),c(1,2),c(2,3)) >> b<-c(10,20,30) >> >> I would like to have a list (like "d") or a vector (like "e") >> as below. >> >> d<-list(c((1+10),(3+10)),c((1+20),(2+20)),c((2+30),(3+30))) >> e<- c((1+10)+(3+10),(1+20)+(2+20),(2+30)+(3+30)) >> >> Thanks, >> >> >> Yongwan Chun >> >> ______________________________________________ >> R-help@stat.math.ethz.ch 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. >> > > ______________________________________________ > R-help@stat.math.ethz.ch 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. > Charles C. Berry (858) 534-2098 Dept of Family/Preventive Medicine E mailto:[EMAIL PROTECTED] UC San Diego http://famprevmed.ucsd.edu/faculty/cberry/ La Jolla, San Diego 92093-0901 ______________________________________________ R-help@stat.math.ethz.ch 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.