R help - May 2012 - subset columns from list with variable substitution

Hi there, I would like to use a list variable to select columns in a subset
from a parent table:

I have a data frame "table" with column headers a,b,c,d,e,x,y,z

and list variables

list1=c("a","b","c","d")
list2=c("a","b","x",y","z")
namelist=c("peter","paul","mary","jane")
group1=c("peter","paul")
group2=c("mary","jane")

I would like to subset "table" based on the list variable in a for
loop:

for (i %in% namelist){
     if (i %in% group1){table2<-subset(table, select=list1)}
     else {{table2<-subset(table, select=list2)}
}

the "select=list1" syntax does not work. What would be the correct way
to do
this?

Many Thanks

Jon

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Instead of
  subset(table, select=list1)
try
  table[, list1]

However, I suspect you have other problems.
Particularly, i is not defined when you use i %in% namelist.
You may have wanted
  i in namelist
  
-Don

-- 
Don MacQueen

Lawrence Livermore National Laboratory
7000 East Ave., L-627
Livermore, CA 94550
925-423-1062





On 5/25/12 11:09 AM, "jween" <jween at rockwoodclinic.com>
wrote:
>Hi there, I would like to use a list variable to select columns in a
>subset
>from a parent table:
>
>I have a data frame "table" with column headers a,b,c,d,e,x,y,z
>
>and list variables
>
>list1=c("a","b","c","d")
>list2=c("a","b","x",y","z")
>namelist=c("peter","paul","mary","jane")
>group1=c("peter","paul")
>group2=c("mary","jane")
>
>I would like to subset "table" based on the list variable in a for
loop:
>
>for (i %in% namelist){
>     if (i %in% group1){table2<-subset(table, select=list1)}
>     else {{table2<-subset(table, select=list2)}
>}
>
>the "select=list1" syntax does not work. What would be the correct
way to
>do
>this?
>
>Many Thanks
>
>Jon
>
>--
>View this message in context:
>http://r.789695.n4.nabble.com/subset-columns-from-list-with-variable-subst
>itution-tp4631374.html
>Sent from the R help mailing list archive at Nabble.com.
>
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