[R] sample

[T. Murlidharan Nair]

Thanks to all for trying to help me with problem. After spending a long 
time, I eventually solved it
by writing a perl script and transposing the matrix and re-reading the 
file. When I did this I got an
error saying I had duplicate row names (which in fact was not true or 
may be something to with
the naming conventions in R).
The column names were  :
Tumor_VA_114-1, Tumor_VA_114-2,.....
But when I changed it to Tumor_VA_114_1, Tumor_VA_114_2 it worked fine.
I was not aware that - cannot be used to differentiate variables. Is 
this the case ?
Sorry, if I wasted any of your time.
Cheers ../Murli



Liaw, Andy wrote:

>?sample says:
>
>x   Either a (numeric, complex, character or logical) vector of more
>    than one element from which to choose, or a positive integer 
>
>so I guess it wasn't meant to be used on a data frame.  However, a data
>frame is a list (where the variables are the components), and a list is a
>vector, so the behavior is consistent:
>
>  
>
>>x <- list("a", 2, "c", 4, "e", "f")
>>sample(x)
>>    
>>
>[[1]]
>[1] "c"
>
>[[2]]
>[1] "a"
>
>[[3]]
>[1] 4
>
>[[4]]
>[1] 2
>
>[[5]]
>[1] "f"
>
>[[6]]
>[1] "e"
>
>Andy
>
>  
>
>>From: Jean Eid
>>
>>It seems that sample picks columns when the object is turned into a
>>data.frame. I do not knoe why it is doing that....
>>
>>Is this something that was meant and not documented or something?
>>
>>
>>Jean
>>
>>
>>On Fri, 11 Feb 2005, Adaikalavan Ramasamy wrote:
>>
>>    
>>
>>>See below.
>>>
>>>On Thu, 2005-02-10 at 14:53 -0800, T. Murlidharan Nair wrote:
>>>      
>>>
>>>>Just to explain my previous mail, here is the output I get.
>>>>
>>>>
>>>> > dim(tissue.exp)
>>>>[1] 1532   20
>>>>        
>>>>
>>>What is this object ? Try class(tissue.exp)
>>>
>>>      
>>>
>>>> > pick<-sample(tissue.exp,5,replace=TRUE)
>>>> > dim(pick)
>>>>[1] 1532    5
>>>>        
>>>>
>>>>From help(sample) :
>>>
>>>    sample(x, size, replace = FALSE, prob = NULL)
>>>
>>>    x: Either a (numeric, complex, character or logical) vector of
>>>       more than one element from which to choose, or a positive
>>>       integer.
>>>
>>>x has to be a vector or positive integer integer. I am not 
>>>      
>>>
>>sure how you
>>    
>>
>>>got "sample" to work on tissue.exp in the first place. Maybe you got
>>>your own version of "sample".
>>>
>>>
>>>      
>>>
>>>> > tissue.exp.t<-t(tissue.exp)
>>>> > dim(tissue.exp.t)
>>>>[1]   20 1532
>>>> > pick<-sample(tissue.exp.t,5,replace=TRUE)
>>>> > dim(pick)
>>>>NULL
>>>>
>>>>--------
>>>>Thanks ../Murli
>>>>
>>>>______________________________________________
>>>>R-help at stat.math.ethz.ch mailing list
>>>>https://stat.ethz.ch/mailman/listinfo/r-help
>>>>PLEASE do read the posting guide! 
>>>>        
>>>>
>>http://www.R-project.org/posting-guide.html
>>    
>>
>>>      
>>>
>>______________________________________________
>>    
>>
>>>R-help at stat.math.ethz.ch mailing list
>>>https://stat.ethz.ch/mailman/listinfo/r-help
>>>PLEASE do read the posting guide! 
>>>      
>>>
>>http://www.R-project.org/posting-guide.html
>>    
>>
>>______________________________________________
>>R-help at stat.math.ethz.ch mailing list
>>https://stat.ethz.ch/mailman/listinfo/r-help
>>PLEASE do read the posting guide! 
>>http://www.R-project.org/posting-guide.html
>>
>>
>>    
>>
>
>
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