[R] Data Frame as Hash Table

[Alan Lue]

Thanks, guys!

Alan


On Sun, May 30, 2010 at 5:35 AM, Marshall Feldman <marsh at uri.edu> wrote:
> Besides data.table, there's the hash package. It does not use data.frame
> type structures but is a bit more flexible.
>
> Marsh Feldman
>
> On 5/30/10 [May 30, 10] 6:00 AM, r-help-request at r-project.org wrote:
>>
>> Message: 40
>> Date: Sun, 30 May 2010 09:24:22 +0100
>> From: Patrick Burns<pburns at pburns.seanet.com>
>> To:r-help at r-project.org,alan.lue at gmail.com
>> Subject: Re: [R] Data Frame as Hash Table
>> Message-ID:<4C0220B6.7090006 at pburns.seanet.com>
>> Content-Type: text/plain; charset=ISO-8859-1; format=flowed
>>
>> You might want to investigate the 'data.table'
>> package.
>>
>> On 30/05/2010 09:03, Alan Lue wrote:
>>
>>>
>>> >  I'm interested in using a data frame as if it were a hash table.  For
>>> >  instance if I had the following,
>>> >
>>>
>>>>
>>>> >>  (d<- data.frame(key=seq(0.5, 3, 0.5), value=rnorm(6)))
>>>>
>>>
>>> >      key        value
>>> >  1 0.5 -1.118665122
>>> >  2 1.0  0.465122921
>>> >  3 1.5 -0.529239211
>>> >  4 2.0 -0.147324638
>>> >  5 2.5 -1.531503795
>>> >  6 3.0 -0.002720434
>>> >
>>> >  Then I'd like to be able to quickly retrieve the "value" of "key" 1.5
>>> >  to get -0.53.  How would one go about doing this?
>>> >
>>> >  Yours,
>>> >  Alan Lue
>>> >
>>> >  ______________________________________________
>>> >  R-help at r-project.org  mailing list
>>> >  https://stat.ethz.ch/mailman/listinfo/r-help
>>> >  PLEASE do read the posting
>>> > guidehttp://www.R-project.org/posting-guide.html
>>> >  and provide commented, minimal, self-contained, reproducible code.
>>> >
>>>
>>
>> -- Patrick Burns pburns at pburns.seanet.com http://www.burns-stat.com (home
>> of 'Some hints for the R beginner' and 'The R Inferno')
>
>



-- 
Alan Lue
Master of Financial Engineering
UCLA Anderson School of Management