On Mon, Jun 9, 2008 at 1:11 PM, Dumblauskas, Jerry <[EMAIL PROTECTED]> wrote: > I've received a couple of responses telling me to use list (I was trying > to use 2 equal length vectors but having an issue pulling out the index > subscript).
Should you ever need to do that for another application, check ?which > I can use lists now, and stop thrashing.... :) > Thx again for the assistance! > > -----Original Message----- > From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Douglas > Bates > Sent: Monday, June 09, 2008 1:08 PM > To: Dumblauskas, Jerry > Cc: r-help@r-project.org > Subject: Re: [R] Basic Question on Keys/Values > > On Mon, Jun 9, 2008 at 12:55 PM, Dumblauskas, Jerry > <[EMAIL PROTECTED]> wrote: >> As a java programmer, I'm having issue conceptualizing the following >> use >> case: > >> Given an value, passed into a function, how do I pull out the lookup? > >> Ie. >> A list of keys (key1, key2, key3) >> A list of values (val1,val2,val3) > >> I want to write a function (or is there something built in?) such that > >> Callit <- (thekey) { >> (magic happens here) >> Return value >> } > > If the keys are text strings then you can use a named list as the > container. > >> foo <- list(a = 1:10, b = LETTERS[1:3], ttt = Formaldehyde) foo$b > [1] "A" "B" "C" >> bar <- "a" >> foo$bar > NULL >> foo[[bar]] > [1] 1 2 3 4 5 6 7 8 9 10 > > Note that the $ operator is an extractor for an explicit name. If you > want the value corresponding to a key which is itself stored as an > object in R you must use the '[[' notation. > > Lists are suitable for a small to moderate number of key/value pairs. > For large numbers of key/value pairs you may want to consider > environments instead. > >> Any ideas? >> >> Thanks a bunch! >> >> ====================================================================== >> ======== Please access the attached hyperlink for an important >> electronic communications disclaimer: >> >> http://www.credit-suisse.com/legal/en/disclaimer_email_ib.html >> ====================================================================== >> ======== >> >> ______________________________________________ >> 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. >> > > ============================================================================== > Please access the attached hyperlink for an important electronic > communications disclaimer: > > http://www.credit-suisse.com/legal/en/disclaimer_email_ib.html > ============================================================================== > > ______________________________________________ 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.
