[R] Sorting data

[arun]

Hi,

Hope this is what you meant.. 

with(dat1,mean(V21[(V2==1|V2==0) & V24<25],na.rm=TRUE))  
#[1] 2.8125
 sapply(0:1,function(i) with(dat1,mean(V21[V2==i & V24<25],na.rm=TRUE)))
#[1] 2.75 3.00



"..... who are in condition 1 or 0 (V2) and then vice 
versa ..."


 dat1[,21]
# [1]   NA 3.40 3.00 3.00   NA 3.00 2.75 2.50 3.30 4.00
 with(dat1,(V21==1|V21==0) & V24<25) #here the condition is not clear..
# [1]    NA FALSE FALSE FALSE    NA FALSE FALSE FALSE FALSE FALSE
 with(dat1,mean(V2[(V21==1|V21==0) & V24<25],na.rm=TRUE)) 
#[1] NaN


A.K.



Hi. 

Thanks for the quick reply.   

To clarify, I'm interested in V21 (which is GPA) but I want to 
look at it for people who are in condition 1 or 0 (V2) and then vice 
versa, furthermore, I want to further filter for it to be people who are
 under 25 (V24).  So to sum up, I want to see what the GPA is for people
 in condition 1 who are under 25.  Hope this makes sense. 

The data set is actually 158 rows with 25 columns for now, and will include 300+ more participants.     



----- Original Message -----
From: arun <smartpink111 at yahoo.com>
To: R help <r-help at r-project.org>
Cc: 
Sent: Sunday, August 25, 2013 9:20 PM
Subject: Re: Sorting data



Hi,
It's not clear what you really wanted.  May be this helps:

dat1<- read.table(text="
  V1 V2 V3 V4 V5 V6 V7 V8 V9 V10 V11 V12 V13 V14 V15 V16 V17 V18 V19 V20   V21 V22 V23 V24 V25 V26
1     1  1  3  1 NA NA  1 NA NA   1   2   7   5   3   2 1.0  15  17   5   1    NA   1   2  19   1   1
2     2  0  1  1 NA NA  1 NA NA   1  NA  NA   5  NA  NA 3.0  NA  NA   3   5 3.400   1   2  39   1   1
3     3  1  2  2 NA NA  2 NA NA   2   1  NA   5   5  NA 2.0   3  NA   5  NA 3.000   2   5  19   1   3
4     4  0  1  1 NA NA  1 NA NA   1  NA  NA   5  NA  NA 2.0  NA  NA   5  NA 3.000   2   2  17   1   2
5     5  1  2  9 NA NA  1 NA NA   1   9  NA   5   3  NA 3.0   3  NA   4  NA    NA   1   6  17   1   1
6     6  1  2  1 NA NA  1 NA NA   1  10  NA   5   3  NA 3.0   5  NA   4  NA 3.000   1   8  32   1   1
7     7  0  1  1 NA NA  1 NA NA   1  NA  NA   5  NA  NA 2.0  NA  NA   3   1 2.750   1   9  20   1   1
8     8  0  1  1 NA NA  1 NA NA   1  NA  NA   5  NA  NA 2.0  NA  NA   4   4 2.500   1   2  21   1   1
9     9  0  2  1 NA NA  1 NA NA   1   2  NA   5   2  NA 3.0  NA  NA   4   2 3.300   1   2  29   1   1
10   10  0  1  1 NA NA  1 NA NA   1  NA  NA   5  NA  NA 2.0  NA  NA   4  NA 4.000   2   2  28   2   2
",sep="",header=TRUE)
with(dat1,mean(V21[(V2==1) & V24>25],na.rm=TRUE))
#[1] 3


A.K.



I'm trying to sort data depending on multiple variables.  For example, I want to get V21 mean based on V2 = 1 (condition) and V24 >25 
(age).   


   V1 V2 V3 V4 V5 V6 V7 V8 V9 V10 V11 V12 V13 V14 V15 V16 V17 V18 V19 V20   V21 V22 V23 V24 V25 V26 
1     1  1  3  1 NA NA  1 NA NA   1   2   7   5   3   2 1.0  15  17   5   1    NA   1   2  19   1   1 
2     2  0  1  1 NA NA  1 NA NA   1  NA  NA   5  NA  NA 3.0  NA  NA   3   5 3.400   1   2  39   1   1 
3     3  1  2  2 NA NA  2 NA NA   2   1  NA   5   5  NA 2.0   3  NA   5  NA 3.000   2   5  19   1   3 
4     4  0  1  1 NA NA  1 NA NA   1  NA  NA   5  NA  NA 2.0  NA  NA   5  NA 3.000   2   2  17   1   2 
5     5  1  2  9 NA NA  1 NA NA   1   9  NA   5   3  NA 3.0   3  NA   4  NA    NA   1   6  17   1   1 
6     6  1  2  1 NA NA  1 NA NA   1  10  NA   5   3  NA 3.0   5  NA   4  NA 3.000   1   8  32   1   1 
7     7  0  1  1 NA NA  1 NA NA   1  NA  NA   5  NA  NA 2.0  NA  NA   3   1 2.750   1   9  20   1   1 
8     8  0  1  1 NA NA  1 NA NA   1  NA  NA   5  NA  NA 2.0  NA  NA   4   4 2.500   1   2  21   1   1 
9     9  0  2  1 NA NA  1 NA NA   1   2  NA   5   2  NA 3.0  NA  NA   4   2 3.300   1   2  29   1   1 
10   10  0  1  1 NA NA  1 NA NA   1  NA  NA   5  NA  NA 2.0  NA  NA   4  NA 4.000   2   2  28   2   2 


I have tried numerous equations, but they don't give me what I need. 

Help is greatly appreciated.