Thanks for the suggestions, but 'cat' is not causing name space conflicts
for me and since I'm not packaging the code for anyone else to use, I'm less
than concerned about potential conflicts. I did type that too quickly, and I
have resolved my problem using a workaround that does not involve finding
the names of top level list objects based on comparisons, but to clarify for
anyone who is interested;

adataframe[ i, c('cat','result') ] <- c( i, result)

allows me to assign the variable 'i' to the df column 'cat' and 'result' to
the df column 'result' simultaneously for the ith entry (of course where 'i'
is the row number). It just happens to be the case that 'i' is both the db
key and the row name in the df, but since other portions of my code are
shuffling the list I'm using to eventually fill the df it makes more sense
for me to keep track of everything with the db key ('cat') than to try and
use list indexes to keep track of where data is going. The solution I'm
using is like this;

for (i in npu_pdf_bw) {
        prob <-
fitted(npudist(bw=i[[2]],bwmethod="normal-reference",edat=origin[cols_select]))
        print(prob)
        pdf_pred[i[[1]],c('cat','probability')] <- c(i[[1]],prob)
}

where npu_pdf_bw is a list of lists that each contains the 'cat' db key and
an associated 'np' bandwidth object. 'pdf_pred' is a dataframe that holds
the values and allows me to search for the result ('prob') on the basis of
the 'cat' column thus maintaining my database integrity. It's perfectly
acceptable for you to choose not to offer support on a volunteer help
mailing list and I'm certain that support offered, when bitter or scathing,
isn't appreciated in any event.

C

On 15 November 2010 17:59, David Winsemius <dwinsemius@comcast.net> wrote:

>
> On Nov 15, 2010, at 5:07 PM, Chris Carleton wrote:
>
>  Thanks for the suggestions. The issue for me is that the top level index
>> is
>> also like a database key so it might be a bit annoying to coerce it to
>> char() so that I can reference it with a $ and then I would have to still
>> be
>> able to find out what the name was automatically. I've got a function
>> right
>> now that iterates through a list of values (db keys called cat values in
>> this case) that returns an object from another function that will be used
>> in
>> yet another function. So, I have to store the objects and then pass each
>> one
>> in turn to a function while keeping track of what cat value that object is
>> associated with so that it can be stored in relation to the cat value in a
>> dataframe. Essentially like this...
>>
>> for i in cat {
>>
>
> Please do not use "cat" as an object name for the same reason as not to use
> "c" or "data" as object names.
>
>
>  object <- somefunction()
>> alist[[ i ]] <- object
>> }
>>
>> for i in cat {
>> result <- somefunction(object[[ i ]])
>> adataframe[[ i, c('cat','result') ]] <- c( i, result)
>>
>
> I don't think the [[ operator take two arguments. Perhaps you meant to use
> the "[" operator. Even then cannot tell what "cat" is supposed to be and
> quoteing cat would prevent it from being evaluated.
>
>
>  }
>>
>> I'm paranoid about loosing track of which cat value is associated with
>> which
>> result and that's why I'm looking for a way to ensure that the output is
>> stored correctly. The whole thing is going to be automated. Any
>> suggestions
>> would definitely be appreciated. I've tried just creating a list of lists
>> to
>> keep track of things so that list[[1]][[1]] is the cat value and
>> list[[1]][[2]] is the associated object, but now I'm having trouble
>> passing
>> the object to the next function. This might take some time for me to work
>> out.
>>
>
> It appears you are too busy to make a working example, so I am too busy to
> do it for you.
>
> ?names  # for naming  and access to names of list elements
>
> --
> David.
>
>
>
>
>>
>> Thanks,
>>
>> Chris
>>
>>
>> On 15 November 2010 16:38, Joshua Wiley <jwiley.psych@gmail.com> wrote:
>>
>>  Hi Chris,
>>>
>>> Does this do what you're after?  It just compares each element of a
>>> (i.e., a[[1]] and a[[2]]) to c(1, 2) and determines if they are
>>> identical or not.
>>>
>>> which(sapply(a, identical, y = c(1, 2)))
>>>
>>> There were too many 1s floating around for me to figure out if you
>>> wanted to find elements of a that matched the entire vector or
>>> subelements of a that matched elements of the vector (if that makes
>>> any sense).
>>>
>>> HTH,
>>>
>>> Josh
>>>
>>> On Mon, Nov 15, 2010 at 1:24 PM, Chris Carleton
>>> <w_chris_carleton@hotmail.com> wrote:
>>>
>>>> Hi List,
>>>>
>>>> I'm trying to work out how to use which(), or another function, to find
>>>>
>>> the
>>>
>>>> top-level index of a list item based on a condition. An example will
>>>>
>>> clarify
>>>
>>>> my question.
>>>>
>>>> a <- list(c(1,2),c(3,4))
>>>> a
>>>> [[1]]
>>>> [1] 1 2
>>>>
>>>> [[2]]
>>>> [1] 3 4
>>>>
>>>> I want to find the top level index of c(1,2), which should return 1
>>>>
>>> since;
>>>
>>>>
>>>> a[[1]]
>>>> [1] 1 2
>>>>
>>>> I can't seem to work out the syntax. I've tried;
>>>>
>>>> which(a == c(1,2))
>>>>
>>>> and an error about coercing to double is returned. I can find the index
>>>>
>>> of
>>>
>>>> elements of a particular item by
>>>>
>>>> which(a[[1]]==c(1,2)) or which(a[[1]]==1) etc that return [1] 1 2 and
>>>> [1]
>>>>
>>> 1
>>>
>>>> respectively as they should. Any thoughts?
>>>>
>>>> C
>>>>
>>>>      [[alternative HTML version deleted]]
>>>>
>>>> ______________________________________________
>>>> R-help@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.
>>>>
>>>>
>>>
>>>
>>> --
>>> Joshua Wiley
>>> Ph.D. Student, Health Psychology
>>> University of California, Los Angeles
>>> http://www.joshuawiley.com/
>>>
>>>
>>>
>>        [[alternative HTML version deleted]]
>>
>> ______________________________________________
>> R-help@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.
>>
>
> David Winsemius, MD
> West Hartford, CT
>
>

	[[alternative HTML version deleted]]

