Thanks, but I tried the single ampersand, but got a warning msg with
the same lack of correct assignment:
> if (das$age>65 & das$bmi>30) {das$danger<-1} else das$danger<-0
Warning message:
In if (das$age > 65 & das$bmi > 30) { :
the condition has length > 1 and only the first element will be used
> attach(das)
The following object(s) are masked from das ( position 3 ) :
age bmi day id male sex status
> das
id age sex bmi status day male danger
1 33001 35 M 27.5 0 365 1 0
2 33002 29 M 34.9 1 22 1 0
3 33003 41 F 23.6 0 365 0 0
4 33004 55 F 27.0 0 365 0 0
5 42001 37 M 39.0 0 365 1 0
6 42002 53 M 26.6 1 124 1 0
7 42003 46 F 45.4 1 287 0 0
8 42004 35 F 36.2 0 365 0 0
9 42005 38 F 24.6 0 365 0 0
10 42006 58 F 28.0 0 365 0 0
11 42007 27 M 25.0 0 365 1 0
12 42008 65 F 24.6 0 365 0 0
13 42009 25 F 28.0 0 365 0 0
14 43001 66 M 27.8 0 365 1 0
15 43002 57 F 34.0 0 365 0 0
16 43003 45 F 38.1 0 365 0 0
17 43004 33 F 53.3 1 62 0 0
18 43005 56 F 36.5 0 365 0 0
19 43006 31 F 22.4 1 1 0 0
20 43007 53 F 32.2 1 21 0 0
21 55001 51 M 29.2 0 365 1 0
22 55002 33 F 18.7 0 365 0 0
23 55003 40 F 30.3 0 365 0 0
24 55004 67 M 31.9 0 365 1 0 <-
25 55005 41 F 35.0 0 365 0 0
26 55006 44 F 37.3 0 365 0 0
27 55007 67 M 28.4 1 1 1 0
28 55008 65 F 28.8 0 365 0 0
29 55009 76 M 18.8 1 225 1 0
30 55010 75 F 21.1 1 39 0 0
31 63001 30 F 24.9 0 365 0 0
32 63002 36 F 47.2 1 377 0 0
33 63003 45 F 32.0 0 365 0 0
34 63004 49 F 32.3 0 365 0 0
35 63005 41 F 20.2 0 365 0 0
36 63006 60 F 28.2 0 365 0 0
37 63007 33 F 24.5 0 365 0 0
38 63008 36 F 28.4 1 56 0 0
39 63009 31 F 22.1 0 365 0 0
40 63010 77 M 26.6 1 9 1 0
41 63011 41 F 32.0 0 365 0 0
42 63012 40 F 38.5 1 92 0 0
43 63013 27 M 20.6 0 365 1 0
At 02:11 PM 1/1/2008, Christos Hatzis wrote:
>You need to use '&' instead of '&&':
>
>A shorter version of your code using ifelse:
>
>das$danger <- with(das, ifelse(age>65 & bmi>30, 1, 0))
>
>HTH
>
>-Christos
>
> > -----Original Message-----
> > From: [EMAIL PROTECTED]
> > [mailto:[EMAIL PROTECTED] On Behalf Of Gerard Smits
> > Sent: Tuesday, January 01, 2008 5:04 PM
> > To: r-help@r-project.org
> > Subject: [R] if statement problem
> >
> > Hi All,
> >
> > I have a small dataset named das (43 cases) in which I am
> > trying to create a binary outcome (1/0) based on the following code:
> >
> > if (das$age>65 && das$bmi>30) {das$danger<-1} else das$danger<-0
> >
> > I am setting a flag called 'danger' to 1 of the subject is
> > over 65 and has a BMI > 30.
> >
> > I find that my statement evaluates the first record in the
> > data.frame and then carries that assignment for all. I
> > detected this as I played around with the values and found
> > that the T/F status of the first record was always carried
> > dowqn. I have gotten this to work with an elseif
> > construction, but would like to know what is happening here.
> >
> > Thanks,
> >
> > Gerard
> >
> > Using: Windows Vista and R 2.61
> >
> >
> > Code and output:
> >
> > das<- sasxport.get("c:\\personal\\r\\das.xpt")
> > if (das$age>65 && das$bmi>30) {das$danger<-1} else das$danger<-0
> > attach(das)
> > das
> >
> >
> > The following object(s) are masked from das ( position 3 ) :
> >
> > age bmi day id male sex status
> >
> > id age sex bmi status day male danger
> > 1 33001 35 M 27.5 0 365 1 0
> > 2 33002 29 M 34.9 1 22 1 0
> > 3 33003 41 F 23.6 0 365 0 0
> > 4 33004 55 F 27.0 0 365 0 0
> > 5 42001 37 M 39.0 0 365 1 0
> > 6 42002 53 M 26.6 1 124 1 0
> > 7 42003 46 F 45.4 1 287 0 0
> > 8 42004 35 F 36.2 0 365 0 0
> > 9 42005 38 F 24.6 0 365 0 0
> > 10 42006 58 F 28.0 0 365 0 0
> > 11 42007 27 M 25.0 0 365 1 0
> > 12 42008 65 F 24.6 0 365 0 0
> > 13 42009 25 F 28.0 0 365 0 0
> > 14 43001 66 M 27.8 0 365 1 0
> > 15 43002 57 F 34.0 0 365 0 0
> > 16 43003 45 F 38.1 0 365 0 0
> > 17 43004 33 F 53.3 1 62 0 0
> > 18 43005 56 F 36.5 0 365 0 0
> > 19 43006 31 F 22.4 1 1 0 0
> > 20 43007 53 F 32.2 1 21 0 0
> > 21 55001 51 M 29.2 0 365 1 0
> > 22 55002 33 F 18.7 0 365 0 0
> > 23 55003 40 F 30.3 0 365 0 0
> > 24 55004 67 M 31.9 0 365 1 0 <- Problem case should
> > =1 for danger
> > 25 55005 41 F 35.0 0 365 0 0
> > 26 55006 44 F 37.3 0 365 0 0
> > 27 55007 67 M 28.4 1 1 1 0
> > 28 55008 65 F 28.8 0 365 0 0
> > 29 55009 76 M 18.8 1 225 1 0
> > 30 55010 75 F 21.1 1 39 0 0
> > 31 63001 30 F 24.9 0 365 0 0
> > 32 63002 36 F 47.2 1 377 0 0
> > 33 63003 45 F 32.0 0 365 0 0
> > 34 63004 49 F 32.3 0 365 0 0
> > 35 63005 41 F 20.2 0 365 0 0
> > 36 63006 60 F 28.2 0 365 0 0
> > 37 63007 33 F 24.5 0 365 0 0
> > 38 63008 36 F 28.4 1 56 0 0
> > 39 63009 31 F 22.1 0 365 0 0
> > 40 63010 77 M 26.6 1 9 1 0
> > 41 63011 41 F 32.0 0 365 0 0
> > 42 63012 40 F 38.5 1 92 0 0
> > 43 63013 27 M 20.6 0 365 1 0
> >
> > [[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.
> >
> >
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