[R] Help using Cast (Text) Version

[David Winsemius]

On Jan 17, 2010, at 11:56 AM, Steve Sidney wrote:

> David
>
> Thanks, I'll try that......but no what I need is the total (1's) for  
> each of the rows, labelled 1-6 at the top of each col in the table  
> provided.

Part of my confusion with your request (which remains unaddressed) is  
what you mean by "valid". The melt-cast operation has turned a bunch  
of NA's into 0's which are now indistinguishable from the original  
0's. So I don't see any way that operating on "b" could tell you the  
numbers you are asking for. If you were working on the original data,  
"res", you might have gotten the column-wise "valid" counts of column  
2 with something like:

  sum( !is.na(res[,2]) )

>
> What I guess I am not sure of is how to identify the col after the  
> melt and cast.

The cast object represents columns as a list of vectors. The i-th  
column is b[[i]] which could be further referenced as a vector. So the  
j-th row entry for the i-th column would be b[[i]][j].


>
> Steve
>
> ----- Original Message ----- From: "David Winsemius" <dwinsemius at comcast.net 
> >
> To: "Steve Sidney" <sbsidney at mweb.co.za>
> Cc: <r-help at r-project.org>
> Sent: Sunday, January 17, 2010 4:39 PM
> Subject: Re: [R] Help using Cast (Text) Version
>
>
>>
>> On Jan 17, 2010, at 5:31 AM, Steve Sidney wrote:
>>
>>> Sorry to repeat the meassage, not sure if the HTML version has  
>>> been received - Apologies for duplication
>>>
>>> Dear list
>>>
>>> I am trying to count the no of occurances in a column of a data   
>>> frame and there is missing data identifed by NA.
>>>
>>> I am able to melt and cast the data correctly as well as sum the  
>>> occurances using margins and sum.
>>>
>>> Here are the melt and cast commands
>>>
>>> bw = melt(res, id=c("lab","r"), "pf_zbw")
>>> b = cast(bw, lab ~ r, sum, margins = T)
>>>
>>> Sample Data (before using sum and margins)
>>>
>>>   lab  1  2  3  4  5  6
>>> 1  4er66  1 NA  1  0 NA  0
>>> 2  4gcyi  0  0  1  0  0  0
>>> 3  5d3hh  0  0  0 NA  0  0
>>> 4  5d3wt  0  0  0  0  0  0
>>> .
>>> . lines deleted to save space
>>> .
>>> 69 v3st5 NA NA  1 NA NA NA
>>> 70 a22g5 NA  0 NA NA NA NA
>>> 71 b5dd3 NA  0 NA NA NA NA
>>> 72 g44d2 NA  0 NA NA NA NA
>>>
>>> Data after using sum and margins
>>>
>>>   lab 1 2 3 4 5 6 (all)
>>> 1  4er66 1 0 1 0 0 0     2
>>> 2  4gcyi 0 0 1 0 0 0     1
>>> 3  5d3hh 0 0 0 0 0 0     0
>>> 4  5d3wt 0 0 0 0 0 0     0
>>> 5  6n44r 0 0 0 0 0 0     0
>>> .
>>> .lines deleted to save space
>>> .
>>> 70 a22g5 0 0 0 0 0 0     0
>>> 71 b5dd3 0 0 0 0 0 0     0
>>> 72 g44d2 0 0 0 0 0 0     0
>>> 73 (all) 5 2 4 3 5 7    26
>>>
>>> Uisng length just tells me how many total rows there are.
>>
>>
>>> What I need to do is count how many rows there is valid data, in   
>>> this case either a one (1) or a zero (0) in b
>>
>> I'm guessing that you mean to apply that test to the column in b   
>> labeled "(all)" . If that's the case, then something like  
>> (obviously  untested):
>>
>> sum( b$'(all)' == 1 | b$'(all)' == 0)
>>
>>
>>
>>>
>>> I have a report to construct for tomorrow Mon so any help would be  
>>> appreciated
>>>
>>> Regards
>>> Steve
>>
>> David Winsemius, MD
>> Heritage Laboratories
>> West Hartford, CT
>>
>

David Winsemius, MD
Heritage Laboratories
West Hartford, CT