[R] using lapply with recode

[arun]

HI,

Sorry, I didn't know that "prov" exists in different columns.

Try this:
#changed your example dataset to include one more column and reordered the columns in list elements

mylist<-list(df1=data.frame(a=seq(1,10,1), b=sample(1:15,10,replace=FALSE),prov=c(rep('QUE', 5), rep('BC', 5))), df2=data.frame(prov=c(rep('Quebec', 5), rep('AB', 5)),a=seq(1,10,1),b=sample(1:25,10,replace=FALSE)))


res<-lapply(mylist,function(x) data.frame(x[colnames(x)!="prov"],prov=recode(x$prov,"'QUE'='QC';'Quebec'='QC'")))

 res
#$df1
 #   a  b prov
#1   1  9   QC
#2   2  8   QC
#3   3  1   QC
#4   4  7   QC
#5   5 15   QC
#6   6 10   BC
#7   7  6   BC
#8   8 11   BC
#9   9  5   BC
#10 10 14   BC

#$df2
 #   a  b prov
#1   1 23   QC
#2   2 16   QC
#3   3 12   QC
#4   4 14   QC
#5   5 17   QC
#6   6  7   AB
#7   7  6   AB
#8   8 21   AB
#9   9  5   AB
#10 10  1   AB


A.K.

----- Original Message -----
From: Simon Kiss <sjkiss at gmail.com>
To: arun <smartpink111 at yahoo.com>
Cc: 
Sent: Friday, November 9, 2012 9:39 AM
Subject: Re: [R] using lapply with recode

Hi there:
None of these suggestions do the work. I tried Jim's suggestion and it returns the following:

####
$df1
    a prov
1   1  QUE
2   2  QUE

#####
$df2
    a   prov
1   1 Quebec
2   2 Quebec

So it didn't actually do the recode.  Arun's first suggestion returned the same problem. And his second suggestion won't work because in the original data set the variable "prov" exists in different columns; I can't use the same column subscript to access each column.
Simon Kiss
On 2012-11-08, at 10:43 PM, arun wrote:

> HI,
> 
> Sorry, I gave the wrong answer.  res<-lapply(mylist,function(x) data.frame(a=x[,1],prov=recode(x[,2],"'QUE'='QC';'Quebec'='QC'")))
> res[[1]][1:6,]
> #  a prov
> #1 1   QC
> #2 2   QC
> #3 3   QC
> #4 4   QC
> #5 5   QC
> #6 6   BC
> A.K.
> 
> 
> 
> ----- Original Message -----
> From: Simon Kiss <sjkiss at gmail.com>
> To: r-help at r-project.org
> Cc: 
> Sent: Thursday, November 8, 2012 10:06 PM
> Subject: [R] using lapply with recode
> 
> Hello: 
> Forgive me, this is surely a simple question but I can't figure it out, having consulted the help archives and "Data Manipulation With R" (Spector).
> I have a list of 11 data frames with one common variable in each (prov). I'd like to use lapply to go through and recode one particular level of that common variable. 
> I can get the recode to work, but it only returns the variable that has been recoded.  I need the whole data frame with the recoded variable.
> 
> Thank you for your help. Reproducible data and my current code are below.
> 
> 
> ####Sample Data
> mylist<-list(df1=data.frame(a=seq(1,10,1), prov=c(rep('QUE', 5), rep('BC', 5))), df2=data.frame(a=seq(1,10,1), prov=c(rep('Quebec', 5), rep('AB', 5))))
> str(mylist)
> 
> ###My current code
> lapply(mylist, function(x) {
> recode(x$prov, "'QUE'='QC' ; 'Quebec'='QC'")
> }
> )
> 
> *********************************
> Simon J. Kiss, PhD
> Assistant Professor, Wilfrid Laurier University
> 73 George Street
> Brantford, Ontario, Canada
> N3T 2C9
> 
> ______________________________________________
> 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.
> 

*********************************
Simon J. Kiss, PhD
Assistant Professor, Wilfrid Laurier University
73 George Street
Brantford, Ontario, Canada
N3T 2C9
Cell: +1 905 746 7606

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