R help - May 2012 - Problem with function

Hi,

I'm new to R, so apologies in advance for the triviality of this question,
but I was wondering if anyone could tell me why this function doesn't return
the expected output, i.e. a matrix containing two columns from a large data
frame called 'finalTable'? Oddly, the statement between the curly
brackets
works if run with 'thisCol' and 'thatCol' already defined. Any
help would be
much appreciated.



Here's what 'finalTable' looks like, if it helps:-



Many thanks, Adam

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Hello,

There's nothing wrong with having 'thisCol' and 'thatCol'
already defined or
not.
The problem is that your function does NOT return a value. Get rid of the
assignment and it will work.


CompFunct <- function(thisCol, thatCol) {cbind(finalTable[, thisCol],
finalTable[, thatCol])}


I would also include a data.frame argument,

CompFunct2 <- function(x, thisCol, thatCol) {cbind(x[, thisCol], x[,
thatCol])}
CompFunct2(finalTable, 2, 3)

(But the function is so simple that maybe it's purpose is to save some
keystrokes.)


Hope this helps,

Rui Barradas

acnunn wrote
> 
> Hi,
> 
> I'm new to R, so apologies in advance for the triviality of this
question,
> but I was wondering if anyone could tell me why this function doesn't
> return the expected output, i.e. a matrix containing two columns from a
> large data frame called 'finalTable'? Oddly, the statement between
the
> curly brackets works if run with 'thisCol' and 'thatCol'
already defined.
> Any help would be much appreciated.
> 
> 
> 
> Here's what 'finalTable' looks like, if it helps:-
> 
> 
> 
> Many thanks, Adam
> 

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On May 21, 2012, at 5:13 PM, acnunn wrote:
> Hi,
>
> I'm new to R, so apologies in advance for the triviality of this  
> question,
> but I was wondering if anyone could tell me why this function  
> doesn't return
> the expected output, i.e. a matrix containing two columns from a  
> large data
> frame called 'finalTable'? Oddly, the statement between the curly  
> brackets
> works if run with 'thisCol' and 'thatCol' already defined.
Any help
> would be
> much appreciated.
>
>
Nothing there.
>
> Here's what 'finalTable' looks like, if it helps:-
>
>
Nothing to look at here, either.

You have managed to find an even more obscure method of not presenting  
information than is usual for Nabble postings.

--
David Winsemius, MD
West Hartford, CT