[R] Converting data.frame from long to wide format

[Phil Spector]

Another way, using just base R is

> reshape(df,idvar='y',timevar='x',v.names='z',direction='wide')
   y z.A z.B z.C
1 D   a   b   c
4 E   d   e   f
7 F   g   h   i

 					- Phil Spector
 					 Statistical Computing Facility
 					 Department of Statistics
 					 UC Berkeley
 					 spector at stat.berkeley.edu



On Wed, 8 Dec 2010, Matthew Pettis wrote:

> Hi Jonathan,
>
> Thank you very much!  I was about to recall this after I found this
> discussion (https://stat.ethz.ch/pipermail/r-help/2008-June/164440.html),
> but I think your solution is more tidy.
>
> Thank you very much!
> Matt
>
> On Wed, Dec 8, 2010 at 8:33 PM, Jonathan Christensen <dzhonatan at gmail.com>wrote:
>
>> Matt,
>>
>> library(reshape2)
>> wide.df <- dcast(df, y ~ x)
>>
>> Works great for me.
>>
>> Jonathan
>>
>>
>> On Wed, Dec 8, 2010 at 7:26 PM, Matthew Pettis <matthew.pettis at gmail.com>
>> wrote:
>>> Hi,
>>>
>>> I was wondering if there is an easy way that I am missing for turning a
>> long
>>> dataframe into a wide one.  Below is sample code that will make what I
>> have
>>> and, in comments, the form of what I want:
>>>
>>>    #   Have: dataframe like 'df'
>>> df <- expand.grid( x=LETTERS[1:3], y=LETTERS[4:6])
>>> df$z <- letters[1:length(df[,1])]
>>>
>>> # Want: data.frame that has following form:
>>> #       A   B   C
>>> #   D   a   b   c
>>> #   E   d   e   f
>>> #   F   g   h   i
>>>
>>>
>>> I looked at 'xtabs' and 'cast' from reshape/reshape2, but unless I'm
>>> misunderstanding something, these will work only for the 'z' column being
>>> numeric, not textual.  Is there an easy way to do this with 'z' being
>>> textual rather than numeric?
>>>
>>> tia,
>>> Matt
>>>
>>>        [[alternative HTML version deleted]]
>>>
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>>>
>>
>
>
>
> -- 
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>
> ______________________________________________
> 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.
>