[R] About name of list elements

[Peter Ehlers]

To the OP:

Sooner or later most R beginners are bitten by this all too
convenient shortcut. As an R newbie, think of R as your
bank account: overuse of $-extraction can lead to undesirable
consequences. It's best to acquire the '[[' and '[' habit early.

Peter Ehlers


On 2013-03-25 12:43, Bert Gunter wrote:
> Hello Starter
>
> Before posting, please read relevant Help files!
>
> ?"$"
>
> where it tells you:
>
> "x$name is equivalent to x[["name", exact = FALSE]]. Also, the partial
> matching behavior of [[ can be controlled using the exact argument."
> ..etc.
>
> -- Bert
>
>
>
> On Mon, Mar 25, 2013 at 12:21 PM, Andrew Lin <hlin09pu at gmail.com> wrote:
>
>> Hi folks,
>>
>> I am starter for R. While I tried list as following:
>>
>>> l <- list()
>>> l$foo
>> NULL
>>> l$foobar <- 1
>>> l$foo
>> [1] 1
>>
>> Apparently, foo and foobar are different name for elements in list
>> (actually
>> foo does not exist). But why they are sharing same value?
>>
>> Thanks a lot!
>>
>> Max
>>
>>          [[alternative HTML version deleted]]
>>
>> ______________________________________________
>> R-help at 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.
>>
>
>
>