lists are like vectors, i.e.,

x <- c("a" = 1, "b" = 2)
path <- "b"
x[path]

the same applies to lists:

lis <- list(a = 1:3)
path <- "a"
lis[path]

I hope it helps.

Best,
Dimitris

----
Dimitris Rizopoulos
Ph.D. Student
Biostatistical Centre
School of Public Health
Catholic University of Leuven

Address: Kapucijnenvoer 35, Leuven, Belgium
Tel: +32/16/336899
Fax: +32/16/337015
Web: http://www.med.kuleuven.ac.be/biostat/
    http://www.student.kuleuven.ac.be/~m0390867/dimitris.htm


----- Original Message ----- From: "michael watson (IAH-C)" <[EMAIL PROTECTED]>
To: <[email protected]>
Sent: Thursday, February 10, 2005 2:35 PM
Subject: [R] Using a number as a name to access a list



Hi

Dumb question time again, for which I apologise.

I have a variable that contains the following numerical text "04010".
This is the name to access a list:


as.list(KEGGPATHID2NAME)$"04010"
[1] "MAPK signaling pathway"

Marvellous!  Except I want to do that when "04010" is assigned to a
variable called path and I can't figure out how to do it!

path <- "04010"

# the original and best
as.list(KEGGPATHID2NAME)$"04010"
[1] "MAPK signaling pathway"

# clearly this doesn't, and shouldn't, work as.list(KEGGPATHID2NAME)$path
NULL

# this produces a string... eval(paste("as.list(KEGGPATHID2NAME)$",path,sep=''))
[1] "as.list(KEGGPATHID2NAME)$04010"

# as does this eval(paste('as.list(KEGGPATHID2NAME)$"',path,'"',sep=''))
[1] "as.list(KEGGPATHID2NAME)$\"04010\""


Whats really annoying is that when everyone mails me the answer, I'm going to have known how obvious it is.... Thanks in advance

Mick
Village Idiot

______________________________________________
[email protected] mailing list
https://stat.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://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html

Reply via email to