[R] Multiple Conditional Tranformations
Greetings,
I'm learning R and I'm stuck on a basic concept: how to specify a
logical condition once and then perform multiple transformations under
that condition. The program below is simplified to demonstrate the goal.
Its results are exactly what I want, but I would like to check the
logical state of gender only once and create both (or any number of)
scores at once.
mystring<-
("id,group,gender,q1,q2,q3,q4
01,1,f,2,2,5,4
02,2,f,2,1,4,5
03,1,f,2,2,4,4
04,2,f,1,1,5,5
05,1,m,4,5,4,
06,2,m,5,4,5,5
07,1,m,3,3,4,5
08,2,m,5,5,5,4")
mydata<-read.table(textConnection(mystring),header=TRUE,sep=",",row.name
s="id")
mydata
#Create score1 so that it differs for males and females:
mydata$score1 <- ifelse( mydata$gender=="f" ,
(mydata$score1 <- (2*mydata$q1)+mydata$q2),
ifelse( mydata$gender=="m",
(mydata$score1 <- (3*mydata$q1)+mydata$q2), NA )
)
mydata
#Create score2 so that it too differs for males and females:
mydata$score2 <- ifelse( mydata$gender=="f" ,
(mydata$score2 <- (2.5*mydata$q1)+mydata$q2),
ifelse( mydata$gender=="m",
(mydata$score2 <- (3.5*mydata$q1)+mydata$q2), NA )
)
mydata
Thanks!
Bob
=
Bob Muenchen (pronounced Min'-chen), Manager
Statistical Consulting Center
U of TN Office of Information Technology
200 Stokely Management Center, Knoxville, TN 37996-0520
Voice: (865) 974-5230
FAX: (865) 974-4810
Email: [EMAIL PROTECTED]
Web: http://oit.utk.edu/scc ,
News: http://listserv.utk.edu/archives/statnews.html
=
[[alternative HTML version deleted]]
__
R-help@stat.math.ethz.ch mailing list
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PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.
Re: [R] Multiple Conditional Tranformations
Mark,
Here's what I get when I try that approach.
Thanks,
Bob
> mydata$score1<-numeric(mydata$q1) #just initializing.
> mydata$score2<-numeric(mydata$q1)
> mydata$score1<-NA
> mydata$score2<-NA
> mydata
group gender q1 q2 q3 q4 score1 score2
1 1 f 2 2 5 4 NA NA
2 2 f 2 1 4 5 NA NA
3 1 f 2 2 4 4 NA NA
4 2 f 1 1 5 5 NA NA
5 1 m 4 5 4 NA NA NA
6 2 m 5 4 5 5 NA NA
7 1 m 3 3 4 5 NA NA
8 2 m 5 5 5 4 NA NA
> mydata$score1[mydata$gender == "f"]<-2*mydata$q1 + mydata$q2
Warning message:
number of items to replace is not a multiple of replacement length
> mydata$score2[mydata$gender == "f"]<-2.5*mydata$q1 + mydata$q2
Warning message:
number of items to replace is not a multiple of replacement length
> mydata$score1[mydata$gender == "m"]<-3*mydata$q1 + mydata$q2
Warning message:
number of items to replace is not a multiple of replacement length
> mydata$score2[mydata$gender == "m"]<-3.5*mydata$q1 + mydata$q2
Warning message:
number of items to replace is not a multiple of replacement length
>
-Original Message-
From: Leeds, Mark (IED) [mailto:[EMAIL PROTECTED]
Sent: Friday, November 24, 2006 8:45 PM
To: Muenchen, Robert A (Bob)
Subject: RE: [R] Multiple Conditional Tranformations
I'm not sure if I understand your question but I don't think you need
iflelse statements.
myscore<-numeric(q1) ( because I'm not sure how to initialize a list so
initialize a vector with q1 elements )
myscore<-NA ( I think this should set all the values in myscore to NA )
myscore[mydata$gender == f]<-2*mydata$q1 + mydata$q2
myscore[mydata$gender == m]<-3*mydata$q1 + mydata$q2
the above should do what you do in the first part of your code but I
don't know if that was your question ?
also, it does it making myscore a vector because I didn't know how to
initialize a list.
Someone else may goive a better solution. I'm no expert.
-Original Message-
From: [EMAIL PROTECTED]
[mailto:[EMAIL PROTECTED] On Behalf Of Muenchen, Robert
A (Bob)
Sent: Friday, November 24, 2006 8:27 PM
To: r-help@stat.math.ethz.ch
Subject: [R] Multiple Conditional Tranformations
Greetings,
I'm learning R and I'm stuck on a basic concept: how to specify a
logical condition once and then perform multiple transformations under
that condition. The program below is simplified to demonstrate the goal.
Its results are exactly what I want, but I would like to check the
logical state of gender only once and create both (or any number of)
scores at once.
mystring<-
("id,group,gender,q1,q2,q3,q4
01,1,f,2,2,5,4
02,2,f,2,1,4,5
03,1,f,2,2,4,4
04,2,f,1,1,5,5
05,1,m,4,5,4,
06,2,m,5,4,5,5
07,1,m,3,3,4,5
08,2,m,5,5,5,4")
mydata<-read.table(textConnection(mystring),header=TRUE,sep=",",row.name
s="id")
mydata
#Create score1 so that it differs for males and females:
mydata$score1 <- ifelse( mydata$gender=="f" ,
(mydata$score1 <- (2*mydata$q1)+mydata$q2),
ifelse( mydata$gender=="m",
(mydata$score1 <- (3*mydata$q1)+mydata$q2), NA )
)
mydata
#Create score2 so that it too differs for males and females:
mydata$score2 <- ifelse( mydata$gender=="f" ,
(mydata$score2 <- (2.5*mydata$q1)+mydata$q2),
ifelse( mydata$gender=="m",
(mydata$score2 <- (3.5*mydata$q1)+mydata$q2), NA )
)
mydata
Thanks!
Bob
=
Bob Muenchen (pronounced Min'-chen), Manager Statistical Consulting
Center U of TN Office of Information Technology 200 Stokely Management
Center, Knoxville, TN 37996-0520
Voice: (865) 974-5230
FAX: (865) 974-4810
Email: [EMAIL PROTECTED]
Web: http://oit.utk.edu/scc <http://oit.utk.edu/scc> ,
News: http://listserv.utk.edu/archives/statnews.html
<http://listserv.utk.edu/archives/statnews.html>
=
[[alternative HTML version deleted]]
__
R-help@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
and provide commented, minimal, self-contained, reproducible code.
This is not an offer (or solicitation of an offer) to buy/sell the
securities/instruments mentioned or an official confirmation. Morgan
Stanley may deal as principal in or own or act as market maker for
securities/instruments mentioned or may advise the issuers. This is not
research and is not from MS Research but it may refer to a research
analyst/research report. Unless indicated, the
Re: [R] Multiple Conditional Tranformations
Mark,
I finally got that approach to work by spreading the logical condition
everywhere. That gets the lengths to match. Still, I can't help but
think there must be a way to specify the logic once per condition.
Thanks,
Bob
mydata$score1<-numeric(mydata$q1) #just initializing.
mydata$score2<-numeric(mydata$q1)
mydata$score1<-NA
mydata$score2<-NA
mydata
mydata$score1[mydata$gender == "f"]<- 2*mydata$q1[mydata$gender=="f"] +
mydata$q2[mydata$gender=="f"]
mydata$score2[mydata$gender == "f"]<-2.5*mydata$q1[mydata$gender=="f"] +
mydata$q2[mydata$gender=="f"]
mydata$score1[mydata$gender == "m"]<-3*mydata$q1[mydata$gender=="m"] +
mydata$q2[mydata$gender=="m"]
mydata$score2[mydata$gender == "m"]<-3.5*mydata$q1[mydata$gender=="m"] +
mydata$q2[mydata$gender=="m"]
mydata
=
Bob Muenchen (pronounced Min'-chen), Manager
Statistical Consulting Center
U of TN Office of Information Technology
200 Stokely Management Center, Knoxville, TN 37996-0520
Voice: (865) 974-5230
FAX: (865) 974-4810
Email: [EMAIL PROTECTED]
Web: http://oit.utk.edu/scc,
News: http://listserv.utk.edu/archives/statnews.html
=
-Original Message-
From: Leeds, Mark (IED) [mailto:[EMAIL PROTECTED]
Sent: Friday, November 24, 2006 8:45 PM
To: Muenchen, Robert A (Bob)
Subject: RE: [R] Multiple Conditional Tranformations
I'm not sure if I understand your question but I don't think you need
iflelse statements.
myscore<-numeric(q1) ( because I'm not sure how to initialize a list so
initialize a vector with q1 elements )
myscore<-NA ( I think this should set all the values in myscore to NA )
myscore[mydata$gender == f]<-2*mydata$q1 + mydata$q2
myscore[mydata$gender == m]<-3*mydata$q1 + mydata$q2
the above should do what you do in the first part of your code but I
don't know if that was your question ?
also, it does it making myscore a vector because I didn't know how to
initialize a list.
Someone else may goive a better solution. I'm no expert.
-Original Message-
From: [EMAIL PROTECTED]
[mailto:[EMAIL PROTECTED] On Behalf Of Muenchen, Robert
A (Bob)
Sent: Friday, November 24, 2006 8:27 PM
To: r-help@stat.math.ethz.ch
Subject: [R] Multiple Conditional Tranformations
Greetings,
I'm learning R and I'm stuck on a basic concept: how to specify a
logical condition once and then perform multiple transformations under
that condition. The program below is simplified to demonstrate the goal.
Its results are exactly what I want, but I would like to check the
logical state of gender only once and create both (or any number of)
scores at once.
mystring<-
("id,group,gender,q1,q2,q3,q4
01,1,f,2,2,5,4
02,2,f,2,1,4,5
03,1,f,2,2,4,4
04,2,f,1,1,5,5
05,1,m,4,5,4,
06,2,m,5,4,5,5
07,1,m,3,3,4,5
08,2,m,5,5,5,4")
mydata<-read.table(textConnection(mystring),header=TRUE,sep=",",row.name
s="id")
mydata
#Create score1 so that it differs for males and females:
mydata$score1 <- ifelse( mydata$gender=="f" ,
(mydata$score1 <- (2*mydata$q1)+mydata$q2),
ifelse( mydata$gender=="m",
(mydata$score1 <- (3*mydata$q1)+mydata$q2), NA )
)
mydata
#Create score2 so that it too differs for males and females:
mydata$score2 <- ifelse( mydata$gender=="f" ,
(mydata$score2 <- (2.5*mydata$q1)+mydata$q2),
ifelse( mydata$gender=="m",
(mydata$score2 <- (3.5*mydata$q1)+mydata$q2), NA )
)
mydata
Thanks!
Bob
=
Bob Muenchen (pronounced Min'-chen), Manager Statistical Consulting
Center U of TN Office of Information Technology 200 Stokely Management
Center, Knoxville, TN 37996-0520
Voice: (865) 974-5230
FAX: (865) 974-4810
Email: [EMAIL PROTECTED]
Web: http://oit.utk.edu/scc <http://oit.utk.edu/scc> ,
News: http://listserv.utk.edu/archives/statnews.html
<http://listserv.utk.edu/archives/statnews.html>
=
[[alternative HTML version deleted]]
__
R-help@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
and provide commented, minimal, self-contained, reproducible code.
This is not an offer (or solicitation of an offer) to buy/sell the
securities/instruments mentioned or an official confirmation. Morgan
Stanley may deal as principal in or own or act as market maker for
securities/instruments mentioned or may advise the issuers. This is not
re
Re: [R] Multiple Conditional Tranformations
Good idea. I'm still getting used to how flexible R is on substitutions
like that! -Bob
-Original Message-
From: Leeds, Mark (IED) [mailto:[EMAIL PROTECTED]
Sent: Friday, November 24, 2006 10:20 PM
To: Muenchen, Robert A (Bob)
Subject: RE: [R] Multiple Conditional Tranformations
You could set temp<-which(my$gender[my$gender == "f"]) and then temp
will have the female indices and
Then you could just put temp everywhere instead of the statement but I
think that's the best you can do.
Definitely, someone will reply and there may be a shorter way that I am
unaware of.
-Original Message-
From: [EMAIL PROTECTED]
[mailto:[EMAIL PROTECTED] On Behalf Of Muenchen, Robert
A (Bob)
Sent: Friday, November 24, 2006 10:09 PM
To: r-help@stat.math.ethz.ch
Subject: Re: [R] Multiple Conditional Tranformations
Mark,
I finally got that approach to work by spreading the logical condition
everywhere. That gets the lengths to match. Still, I can't help but
think there must be a way to specify the logic once per condition.
Thanks,
Bob
mydata$score1<-numeric(mydata$q1) #just initializing.
mydata$score2<-numeric(mydata$q1)
mydata$score1<-NA
mydata$score2<-NA
mydata
mydata$score1[mydata$gender == "f"]<- 2*mydata$q1[mydata$gender=="f"] +
mydata$q2[mydata$gender=="f"]
mydata$score2[mydata$gender == "f"]<-2.5*mydata$q1[mydata$gender=="f"] +
mydata$q2[mydata$gender=="f"]
mydata$score1[mydata$gender == "m"]<-3*mydata$q1[mydata$gender=="m"] +
mydata$q2[mydata$gender=="m"]
mydata$score2[mydata$gender == "m"]<-3.5*mydata$q1[mydata$gender=="m"] +
mydata$q2[mydata$gender=="m"]
mydata
=
Bob Muenchen (pronounced Min'-chen), Manager Statistical Consulting
Center U of TN Office of Information Technology 200 Stokely Management
Center, Knoxville, TN 37996-0520
Voice: (865) 974-5230
FAX: (865) 974-4810
Email: [EMAIL PROTECTED]
Web: http://oit.utk.edu/scc,
News: http://listserv.utk.edu/archives/statnews.html
=========
-Original Message-
From: Leeds, Mark (IED) [mailto:[EMAIL PROTECTED]
Sent: Friday, November 24, 2006 8:45 PM
To: Muenchen, Robert A (Bob)
Subject: RE: [R] Multiple Conditional Tranformations
I'm not sure if I understand your question but I don't think you need
iflelse statements.
myscore<-numeric(q1) ( because I'm not sure how to initialize a list so
initialize a vector with q1 elements )
myscore<-NA ( I think this should set all the values in myscore to NA )
myscore[mydata$gender == f]<-2*mydata$q1 + mydata$q2
myscore[mydata$gender == m]<-3*mydata$q1 + mydata$q2
the above should do what you do in the first part of your code but I
don't know if that was your question ?
also, it does it making myscore a vector because I didn't know how to
initialize a list.
Someone else may goive a better solution. I'm no expert.
-Original Message-
From: [EMAIL PROTECTED]
[mailto:[EMAIL PROTECTED] On Behalf Of Muenchen, Robert
A (Bob)
Sent: Friday, November 24, 2006 8:27 PM
To: r-help@stat.math.ethz.ch
Subject: [R] Multiple Conditional Tranformations
Greetings,
I'm learning R and I'm stuck on a basic concept: how to specify a
logical condition once and then perform multiple transformations under
that condition. The program below is simplified to demonstrate the goal.
Its results are exactly what I want, but I would like to check the
logical state of gender only once and create both (or any number of)
scores at once.
mystring<-
("id,group,gender,q1,q2,q3,q4
01,1,f,2,2,5,4
02,2,f,2,1,4,5
03,1,f,2,2,4,4
04,2,f,1,1,5,5
05,1,m,4,5,4,
06,2,m,5,4,5,5
07,1,m,3,3,4,5
08,2,m,5,5,5,4")
mydata<-read.table(textConnection(mystring),header=TRUE,sep=",",row.name
s="id")
mydata
#Create score1 so that it differs for males and females:
mydata$score1 <- ifelse( mydata$gender=="f" ,
(mydata$score1 <- (2*mydata$q1)+mydata$q2),
ifelse( mydata$gender=="m",
(mydata$score1 <- (3*mydata$q1)+mydata$q2), NA )
)
mydata
#Create score2 so that it too differs for males and females:
mydata$score2 <- ifelse( mydata$gender=="f" ,
(mydata$score2 <- (2.5*mydata$q1)+mydata$q2),
ifelse( mydata$gender=="m",
(mydata$score2 <- (3.5*mydata$q1)+mydata$q2), NA )
)
mydata
Thanks!
Bob
=
Bob Muenchen (pronounced Min'-chen), Manager Statistical Consulting
Center U of TN Office of Information Technology 200 Stokely Management
Center, Knoxville, TN 37996-0520
Voice: (865) 974-5230
FAX: (865) 974-4810
Email: [EMAIL PROTECTED]
Web: http://oit.utk.edu/scc <http://oit.utk.edu/
Re: [R] Multiple Conditional Tranformations
Try this:
transform(mydata,
score1 = (2 + (gender == "m")) * q1 + q2,
score2 = (2.5 + (gender == "m")) * q1 + q2
)
On 11/24/06, Muenchen, Robert A (Bob) <[EMAIL PROTECTED]> wrote:
> Mark,
>
> I finally got that approach to work by spreading the logical condition
> everywhere. That gets the lengths to match. Still, I can't help but
> think there must be a way to specify the logic once per condition.
>
> Thanks,
> Bob
>
> mydata$score1<-numeric(mydata$q1) #just initializing.
> mydata$score2<-numeric(mydata$q1)
> mydata$score1<-NA
> mydata$score2<-NA
> mydata
>
> mydata$score1[mydata$gender == "f"]<- 2*mydata$q1[mydata$gender=="f"] +
>
> mydata$q2[mydata$gender=="f"]
> mydata$score2[mydata$gender == "f"]<-2.5*mydata$q1[mydata$gender=="f"] +
>
> mydata$q2[mydata$gender=="f"]
> mydata$score1[mydata$gender == "m"]<-3*mydata$q1[mydata$gender=="m"] +
> mydata$q2[mydata$gender=="m"]
> mydata$score2[mydata$gender == "m"]<-3.5*mydata$q1[mydata$gender=="m"] +
>
> mydata$q2[mydata$gender=="m"]
> mydata
>
> =
> Bob Muenchen (pronounced Min'-chen), Manager
> Statistical Consulting Center
> U of TN Office of Information Technology
> 200 Stokely Management Center, Knoxville, TN 37996-0520
> Voice: (865) 974-5230
> FAX: (865) 974-4810
> Email: [EMAIL PROTECTED]
> Web: http://oit.utk.edu/scc,
> News: http://listserv.utk.edu/archives/statnews.html
> =
>
>
> -Original Message-
> From: Leeds, Mark (IED) [mailto:[EMAIL PROTECTED]
> Sent: Friday, November 24, 2006 8:45 PM
> To: Muenchen, Robert A (Bob)
> Subject: RE: [R] Multiple Conditional Tranformations
>
> I'm not sure if I understand your question but I don't think you need
> iflelse statements.
>
> myscore<-numeric(q1) ( because I'm not sure how to initialize a list so
> initialize a vector with q1 elements )
>
> myscore<-NA ( I think this should set all the values in myscore to NA )
> myscore[mydata$gender == f]<-2*mydata$q1 + mydata$q2
> myscore[mydata$gender == m]<-3*mydata$q1 + mydata$q2
>
> the above should do what you do in the first part of your code but I
> don't know if that was your question ?
> also, it does it making myscore a vector because I didn't know how to
> initialize a list.
> Someone else may goive a better solution. I'm no expert.
>
>
> -Original Message-
> From: [EMAIL PROTECTED]
> [mailto:[EMAIL PROTECTED] On Behalf Of Muenchen, Robert
> A (Bob)
> Sent: Friday, November 24, 2006 8:27 PM
> To: r-help@stat.math.ethz.ch
> Subject: [R] Multiple Conditional Tranformations
>
> Greetings,
>
>
>
> I'm learning R and I'm stuck on a basic concept: how to specify a
> logical condition once and then perform multiple transformations under
> that condition. The program below is simplified to demonstrate the goal.
> Its results are exactly what I want, but I would like to check the
> logical state of gender only once and create both (or any number of)
> scores at once.
>
>
>
> mystring<-
>
> ("id,group,gender,q1,q2,q3,q4
>
> 01,1,f,2,2,5,4
>
> 02,2,f,2,1,4,5
>
> 03,1,f,2,2,4,4
>
> 04,2,f,1,1,5,5
>
> 05,1,m,4,5,4,
>
> 06,2,m,5,4,5,5
>
> 07,1,m,3,3,4,5
>
> 08,2,m,5,5,5,4")
>
>
>
> mydata<-read.table(textConnection(mystring),header=TRUE,sep=",",row.name
> s="id")
>
> mydata
>
>
>
> #Create score1 so that it differs for males and females:
>
> mydata$score1 <- ifelse( mydata$gender=="f" ,
>
> (mydata$score1 <- (2*mydata$q1)+mydata$q2),
>
> ifelse( mydata$gender=="m",
>
> (mydata$score1 <- (3*mydata$q1)+mydata$q2), NA )
>
> )
>
> mydata
>
>
>
> #Create score2 so that it too differs for males and females:
>
> mydata$score2 <- ifelse( mydata$gender=="f" ,
>
> (mydata$score2 <- (2.5*mydata$q1)+mydata$q2),
>
> ifelse( mydata$gender=="m",
>
> (mydata$score2 <- (3.5*mydata$q1)+mydata$q2), NA )
>
> )
>
> mydata
>
>
>
>
>
> Thanks!
>
> Bob
>
> =
> Bob Muenchen (pronounced Min'-chen), Manager Statistical Consulting
> Center U of TN Office of Information Technology 200 Stokely Management
> Center, Knoxville, TN 37996-0520
> Voice: (865) 974-5230
> FAX: (865) 974-4810
&g
Re: [R] Multiple Conditional Tranformations
And here is a variation:
transform(mydata,
score1 = (2 + (gender == "m")) * q1 + q2,
score2 = score1 + 0.5 * q1
)
or
transform(
transform(mydata, score1 = (2 + (gender == "m")) * q1 + q2),
score2 = score1 + 0.5 * q1
)
On 11/25/06, Gabor Grothendieck <[EMAIL PROTECTED]> wrote:
> Try this:
>
>
> transform(mydata,
> score1 = (2 + (gender == "m")) * q1 + q2,
> score2 = (2.5 + (gender == "m")) * q1 + q2
> )
>
>
> On 11/24/06, Muenchen, Robert A (Bob) <[EMAIL PROTECTED]> wrote:
> > Mark,
> >
> > I finally got that approach to work by spreading the logical condition
> > everywhere. That gets the lengths to match. Still, I can't help but
> > think there must be a way to specify the logic once per condition.
> >
> > Thanks,
> > Bob
> >
> > mydata$score1<-numeric(mydata$q1) #just initializing.
> > mydata$score2<-numeric(mydata$q1)
> > mydata$score1<-NA
> > mydata$score2<-NA
> > mydata
> >
> > mydata$score1[mydata$gender == "f"]<- 2*mydata$q1[mydata$gender=="f"] +
> >
> > mydata$q2[mydata$gender=="f"]
> > mydata$score2[mydata$gender == "f"]<-2.5*mydata$q1[mydata$gender=="f"] +
> >
> > mydata$q2[mydata$gender=="f"]
> > mydata$score1[mydata$gender == "m"]<-3*mydata$q1[mydata$gender=="m"] +
> > mydata$q2[mydata$gender=="m"]
> > mydata$score2[mydata$gender == "m"]<-3.5*mydata$q1[mydata$gender=="m"] +
> >
> > mydata$q2[mydata$gender=="m"]
> > mydata
> >
> > =
> > Bob Muenchen (pronounced Min'-chen), Manager
> > Statistical Consulting Center
> > U of TN Office of Information Technology
> > 200 Stokely Management Center, Knoxville, TN 37996-0520
> > Voice: (865) 974-5230
> > FAX: (865) 974-4810
> > Email: [EMAIL PROTECTED]
> > Web: http://oit.utk.edu/scc,
> > News: http://listserv.utk.edu/archives/statnews.html
> > =
> >
> >
> > -Original Message-
> > From: Leeds, Mark (IED) [mailto:[EMAIL PROTECTED]
> > Sent: Friday, November 24, 2006 8:45 PM
> > To: Muenchen, Robert A (Bob)
> > Subject: RE: [R] Multiple Conditional Tranformations
> >
> > I'm not sure if I understand your question but I don't think you need
> > iflelse statements.
> >
> > myscore<-numeric(q1) ( because I'm not sure how to initialize a list so
> > initialize a vector with q1 elements )
> >
> > myscore<-NA ( I think this should set all the values in myscore to NA )
> > myscore[mydata$gender == f]<-2*mydata$q1 + mydata$q2
> > myscore[mydata$gender == m]<-3*mydata$q1 + mydata$q2
> >
> > the above should do what you do in the first part of your code but I
> > don't know if that was your question ?
> > also, it does it making myscore a vector because I didn't know how to
> > initialize a list.
> > Someone else may goive a better solution. I'm no expert.
> >
> >
> > -Original Message-
> > From: [EMAIL PROTECTED]
> > [mailto:[EMAIL PROTECTED] On Behalf Of Muenchen, Robert
> > A (Bob)
> > Sent: Friday, November 24, 2006 8:27 PM
> > To: r-help@stat.math.ethz.ch
> > Subject: [R] Multiple Conditional Tranformations
> >
> > Greetings,
> >
> >
> >
> > I'm learning R and I'm stuck on a basic concept: how to specify a
> > logical condition once and then perform multiple transformations under
> > that condition. The program below is simplified to demonstrate the goal.
> > Its results are exactly what I want, but I would like to check the
> > logical state of gender only once and create both (or any number of)
> > scores at once.
> >
> >
> >
> > mystring<-
> >
> > ("id,group,gender,q1,q2,q3,q4
> >
> > 01,1,f,2,2,5,4
> >
> > 02,2,f,2,1,4,5
> >
> > 03,1,f,2,2,4,4
> >
> > 04,2,f,1,1,5,5
> >
> > 05,1,m,4,5,4,
> >
> > 06,2,m,5,4,5,5
> >
> > 07,1,m,3,3,4,5
> >
> > 08,2,m,5,5,5,4")
> >
> >
> >
> > mydata<-read.table(textConnection(mystring),header=TRUE,sep=",",row.name
> > s="id")
> >
> > mydata
> >
> >
> >
> > #Create score1 so that it differs for males and females:
> >
> > mydata$score1 <- ifelse( mydata$gender==
Re: [R] Multiple Conditional Tranformations
Gabor, Those are handy variations! Perhaps my brain in still in SAS mode on this. I'm expecting something like the code below that checks for male only once, checks for female only when not male (skipping NAs) and does all formulas under the appropriate conditions. The formulas I made up to keep the code short & may not be as easily modified to let the logical 0/1 values fix them. if gender=="m" then do; Score1=... Score2= ... end; else if gender=="f" then do; Score1=... Score2= ... end; R may not have anything quite like that. R certainly has many other features that SAS lacks. Thanks, Bob = Bob Muenchen (pronounced Min'-chen), Manager Statistical Consulting Center U of TN Office of Information Technology 200 Stokely Management Center, Knoxville, TN 37996-0520 Voice: (865) 974-5230 FAX: (865) 974-4810 Email: [EMAIL PROTECTED] Web: http://oit.utk.edu/scc, News: http://listserv.utk.edu/archives/statnews.html = -Original Message- From: Gabor Grothendieck [mailto:[EMAIL PROTECTED] Sent: Saturday, November 25, 2006 12:39 AM To: Muenchen, Robert A (Bob) Cc: r-help@stat.math.ethz.ch Subject: Re: [R] Multiple Conditional Tranformations And here is a variation: transform(mydata, score1 = (2 + (gender == "m")) * q1 + q2, score2 = score1 + 0.5 * q1 ) or transform( transform(mydata, score1 = (2 + (gender == "m")) * q1 + q2), score2 = score1 + 0.5 * q1 ) On 11/25/06, Gabor Grothendieck <[EMAIL PROTECTED]> wrote: > Try this: > > > transform(mydata, > score1 = (2 + (gender == "m")) * q1 + q2, > score2 = (2.5 + (gender == "m")) * q1 + q2 > ) > > > On 11/24/06, Muenchen, Robert A (Bob) <[EMAIL PROTECTED]> wrote: > > Mark, > > > > I finally got that approach to work by spreading the logical condition > > everywhere. That gets the lengths to match. Still, I can't help but > > think there must be a way to specify the logic once per condition. > > > > Thanks, > > Bob > > > > mydata$score1<-numeric(mydata$q1) #just initializing. > > mydata$score2<-numeric(mydata$q1) > > mydata$score1<-NA > > mydata$score2<-NA > > mydata > > > > mydata$score1[mydata$gender == "f"]<- 2*mydata$q1[mydata$gender=="f"] + > > > > mydata$q2[mydata$gender=="f"] > > mydata$score2[mydata$gender == "f"]<-2.5*mydata$q1[mydata$gender=="f"] + > > > > mydata$q2[mydata$gender=="f"] > > mydata$score1[mydata$gender == "m"]<-3*mydata$q1[mydata$gender=="m"] + > > mydata$q2[mydata$gender=="m"] > > mydata$score2[mydata$gender == "m"]<-3.5*mydata$q1[mydata$gender=="m"] + > > > > mydata$q2[mydata$gender=="m"] > > mydata > > > > = > > Bob Muenchen (pronounced Min'-chen), Manager > > Statistical Consulting Center > > U of TN Office of Information Technology > > 200 Stokely Management Center, Knoxville, TN 37996-0520 > > Voice: (865) 974-5230 > > FAX: (865) 974-4810 > > Email: [EMAIL PROTECTED] > > Web: http://oit.utk.edu/scc, > > News: http://listserv.utk.edu/archives/statnews.html > > = > > > > > > -Original Message- > > From: Leeds, Mark (IED) [mailto:[EMAIL PROTECTED] > > Sent: Friday, November 24, 2006 8:45 PM > > To: Muenchen, Robert A (Bob) > > Subject: RE: [R] Multiple Conditional Tranformations > > > > I'm not sure if I understand your question but I don't think you need > > iflelse statements. > > > > myscore<-numeric(q1) ( because I'm not sure how to initialize a list so > > initialize a vector with q1 elements ) > > > > myscore<-NA ( I think this should set all the values in myscore to NA ) > > myscore[mydata$gender == f]<-2*mydata$q1 + mydata$q2 > > myscore[mydata$gender == m]<-3*mydata$q1 + mydata$q2 > > > > the above should do what you do in the first part of your code but I > > don't know if that was your question ? > > also, it does it making myscore a vector because I didn't know how to > > initialize a list. > > Someone else may goive a better solution. I'm no expert. > > > > > > -Original Message- > > From: [EMAIL PROTECTED] > > [mailto:[EMAIL PROTECTED] On Behalf Of Muenchen, Robert > > A (Bob) > > Sent: Friday, November 24, 2006 8:27 PM &
Re: [R] Multiple Conditional Tranformations
Firstly your outline does not check once, it checks twice. First it check for "m" and then it redundantly checks for "f". On the other hand the two variations in my post do check once. Although substantially longer than the solutions in my prior posts, if you want the style shown in your post try this: mydata2 <- cbind(mydata, score1 = 0, score2 = 0) is.m <- mydata$gender == "m" mydata2[is.m, ] <- transform(mydata[is.m, ], score1 = 3 * q1 + q2, score2 = 3.5 * q1 + q2 ) mydata2[!is.m,] <- transform(mydata2[!is.m, ], score1 = 2 * q1 + q2, score2 = 2.5 * q1 + q2 ) On 11/25/06, Muenchen, Robert A (Bob) <[EMAIL PROTECTED]> wrote: > Gabor, > > Those are handy variations! Perhaps my brain in still in SAS mode on > this. I'm expecting something like the code below that checks for male > only once, checks for female only when not male (skipping NAs) and does > all formulas under the appropriate conditions. The formulas I made up to > keep the code short & may not be as easily modified to let the logical > 0/1 values fix them. > > if gender=="m" then do; > Score1=... > Score2= > ... > end; > else if gender=="f" then do; > Score1=... > Score2= > ... > end; > > R may not have anything quite like that. R certainly has many other > features that SAS lacks. > > Thanks, > Bob > > = > Bob Muenchen (pronounced Min'-chen), Manager > Statistical Consulting Center > U of TN Office of Information Technology > 200 Stokely Management Center, Knoxville, TN 37996-0520 > Voice: (865) 974-5230 > FAX: (865) 974-4810 > Email: [EMAIL PROTECTED] > Web: http://oit.utk.edu/scc, > News: http://listserv.utk.edu/archives/statnews.html > = > > > -----Original Message----- > From: Gabor Grothendieck [mailto:[EMAIL PROTECTED] > Sent: Saturday, November 25, 2006 12:39 AM > To: Muenchen, Robert A (Bob) > Cc: r-help@stat.math.ethz.ch > Subject: Re: [R] Multiple Conditional Tranformations > > And here is a variation: > > transform(mydata, > score1 = (2 + (gender == "m")) * q1 + q2, > score2 = score1 + 0.5 * q1 > ) > > or > > transform( > transform(mydata, score1 = (2 + (gender == "m")) * q1 + q2), > score2 = score1 + 0.5 * q1 > ) > > > On 11/25/06, Gabor Grothendieck <[EMAIL PROTECTED]> wrote: > > Try this: > > > > > > transform(mydata, > > score1 = (2 + (gender == "m")) * q1 + q2, > > score2 = (2.5 + (gender == "m")) * q1 + q2 > > ) > > > > > > On 11/24/06, Muenchen, Robert A (Bob) <[EMAIL PROTECTED]> wrote: > > > Mark, > > > > > > I finally got that approach to work by spreading the logical > condition > > > everywhere. That gets the lengths to match. Still, I can't help but > > > think there must be a way to specify the logic once per condition. > > > > > > Thanks, > > > Bob > > > > > > mydata$score1<-numeric(mydata$q1) #just initializing. > > > mydata$score2<-numeric(mydata$q1) > > > mydata$score1<-NA > > > mydata$score2<-NA > > > mydata > > > > > > mydata$score1[mydata$gender == "f"]<- > 2*mydata$q1[mydata$gender=="f"] + > > > > > > mydata$q2[mydata$gender=="f"] > > > mydata$score2[mydata$gender == > "f"]<-2.5*mydata$q1[mydata$gender=="f"] + > > > > > > mydata$q2[mydata$gender=="f"] > > > mydata$score1[mydata$gender == "m"]<-3*mydata$q1[mydata$gender=="m"] > + > > > mydata$q2[mydata$gender=="m"] > > > mydata$score2[mydata$gender == > "m"]<-3.5*mydata$q1[mydata$gender=="m"] + > > > > > > mydata$q2[mydata$gender=="m"] > > > mydata > > > > > > = > > > Bob Muenchen (pronounced Min'-chen), Manager > > > Statistical Consulting Center > > > U of TN Office of Information Technology > > > 200 Stokely Management Center, Knoxville, TN 37996-0520 > > > Voice: (865) 974-5230 > > > FAX: (865) 974-4810 > > > Email: [EMAIL PROTECTED] > > > Web: http://oit.utk.edu/scc, > > > News: http://listserv.utk.edu/archives/statnews.html > > > = > > > > > > > > > -Original Message- >
Re: [R] Multiple Conditional Tranformations
That's exactly what I'm looking for. Thanks so much for taking the time to do it that way. On the redundancy issue, I think SAS checks the "else if" condition only if the original "if" is false. The check for f when not m I put in only to exclude missing values for gender. Thanks!! Bob -Original Message- From: Gabor Grothendieck [mailto:[EMAIL PROTECTED] Sent: Saturday, November 25, 2006 7:37 AM To: Muenchen, Robert A (Bob) Cc: r-help@stat.math.ethz.ch Subject: Re: [R] Multiple Conditional Tranformations Firstly your outline does not check once, it checks twice. First it check for "m" and then it redundantly checks for "f". On the other hand the two variations in my post do check once. Although substantially longer than the solutions in my prior posts, if you want the style shown in your post try this: mydata2 <- cbind(mydata, score1 = 0, score2 = 0) is.m <- mydata$gender == "m" mydata2[is.m, ] <- transform(mydata[is.m, ], score1 = 3 * q1 + q2, score2 = 3.5 * q1 + q2 ) mydata2[!is.m,] <- transform(mydata2[!is.m, ], score1 = 2 * q1 + q2, score2 = 2.5 * q1 + q2 ) On 11/25/06, Muenchen, Robert A (Bob) <[EMAIL PROTECTED]> wrote: > Gabor, > > Those are handy variations! Perhaps my brain in still in SAS mode on > this. I'm expecting something like the code below that checks for male > only once, checks for female only when not male (skipping NAs) and does > all formulas under the appropriate conditions. The formulas I made up to > keep the code short & may not be as easily modified to let the logical > 0/1 values fix them. > > if gender=="m" then do; > Score1=... > Score2= > ... > end; > else if gender=="f" then do; > Score1=... > Score2= > ... > end; > > R may not have anything quite like that. R certainly has many other > features that SAS lacks. > > Thanks, > Bob > > = > Bob Muenchen (pronounced Min'-chen), Manager > Statistical Consulting Center > U of TN Office of Information Technology > 200 Stokely Management Center, Knoxville, TN 37996-0520 > Voice: (865) 974-5230 > FAX: (865) 974-4810 > Email: [EMAIL PROTECTED] > Web: http://oit.utk.edu/scc, > News: http://listserv.utk.edu/archives/statnews.html > ===== > > > -Original Message- > From: Gabor Grothendieck [mailto:[EMAIL PROTECTED] > Sent: Saturday, November 25, 2006 12:39 AM > To: Muenchen, Robert A (Bob) > Cc: r-help@stat.math.ethz.ch > Subject: Re: [R] Multiple Conditional Tranformations > > And here is a variation: > > transform(mydata, > score1 = (2 + (gender == "m")) * q1 + q2, > score2 = score1 + 0.5 * q1 > ) > > or > > transform( > transform(mydata, score1 = (2 + (gender == "m")) * q1 + q2), > score2 = score1 + 0.5 * q1 > ) > > > On 11/25/06, Gabor Grothendieck <[EMAIL PROTECTED]> wrote: > > Try this: > > > > > > transform(mydata, > > score1 = (2 + (gender == "m")) * q1 + q2, > > score2 = (2.5 + (gender == "m")) * q1 + q2 > > ) > > > > > > On 11/24/06, Muenchen, Robert A (Bob) <[EMAIL PROTECTED]> wrote: > > > Mark, > > > > > > I finally got that approach to work by spreading the logical > condition > > > everywhere. That gets the lengths to match. Still, I can't help but > > > think there must be a way to specify the logic once per condition. > > > > > > Thanks, > > > Bob > > > > > > mydata$score1<-numeric(mydata$q1) #just initializing. > > > mydata$score2<-numeric(mydata$q1) > > > mydata$score1<-NA > > > mydata$score2<-NA > > > mydata > > > > > > mydata$score1[mydata$gender == "f"]<- > 2*mydata$q1[mydata$gender=="f"] + > > > > > > mydata$q2[mydata$gender=="f"] > > > mydata$score2[mydata$gender == > "f"]<-2.5*mydata$q1[mydata$gender=="f"] + > > > > > > mydata$q2[mydata$gender=="f"] > > > mydata$score1[mydata$gender == "m"]<-3*mydata$q1[mydata$gender=="m"] > + > > > mydata$q2[mydata$gender=="m"] > > > mydata$score2[mydata$gender == > "m"]<-3.5*mydata$q1[mydata$gender=="m"] + > > > > > > mydata$q2[mydata$gender=="m"] > > > mydata > > > > > > = > > > Bob Muenchen (pronounced Min'-chen), Ma
Re: [R] Multiple Conditional Tranformations
Here are some additional solutions. It appears that the SAS code is performing
the transformation row by row and for each row the code in your post is
specifying the transformation so if you want to do it that way we
could use 'by'
like this (where this time we have also added NA processing for the gender):
do.call(rbind, by(mydata, 1:nrow(mydata), function(x)
switch(as.character(x$gender),
m = transform(x, score1 = 3*q1+q2, score2 = 3.5*q1+q2),
f = transform(x, score1 = 2*q1+q2, score2 = 2.5*q1+q2),
NA)
))
# or this somewhat longer version:
do.call(rbind, by(mydata, 1:nrow(mydata), function(x) with(x, {
if (is.na(gender)) {
score1 <- score2 <- NA
} else if (gender == "m") {
score1 = 3 * q1 + q2
score2 = 3.5 * q1 + q2
} else if (gender == "f") {
score1 = 2 * q1 + q2
score2 = 2.5 * q1 + q2
}
cbind(x, score1, score2)
})))
On 11/25/06, Muehnchen, Robert A (Bob) <[EMAIL PROTECTED]> wrote:
> That's exactly what I'm looking for. Thanks so much for taking the time
> to do it that way.
>
> On the redundancy issue, I think SAS checks the "else if" condition only
> if the original "if" is false. The check for f when not m I put in only
> to exclude missing values for gender.
>
> Thanks!!
> Bob
>
> -Original Message-
> From: Gabor Grothendieck [mailto:[EMAIL PROTECTED]
> Sent: Saturday, November 25, 2006 7:37 AM
> To: Muenchen, Robert A (Bob)
> Cc: r-help@stat.math.ethz.ch
> Subject: Re: [R] Multiple Conditional Tranformations
>
> Firstly your outline does not check once, it checks twice. First it
> check for "m" and then it redundantly checks for "f". On the other
> hand the two variations in my post do check once.
>
> Although substantially longer than the solutions in my prior posts,
> if you want the style shown in your post try this:
>
> mydata2 <- cbind(mydata, score1 = 0, score2 = 0)
> is.m <- mydata$gender == "m"
>
> mydata2[is.m, ] <- transform(mydata[is.m, ],
> score1 = 3 * q1 + q2,
> score2 = 3.5 * q1 + q2
> )
>
> mydata2[!is.m,] <- transform(mydata2[!is.m, ],
> score1 = 2 * q1 + q2,
> score2 = 2.5 * q1 + q2
> )
>
> On 11/25/06, Muenchen, Robert A (Bob) <[EMAIL PROTECTED]> wrote:
> > Gabor,
> >
> > Those are handy variations! Perhaps my brain in still in SAS mode on
> > this. I'm expecting something like the code below that checks for male
> > only once, checks for female only when not male (skipping NAs) and
> does
> > all formulas under the appropriate conditions. The formulas I made up
> to
> > keep the code short & may not be as easily modified to let the logical
> > 0/1 values fix them.
> >
> > if gender=="m" then do;
> > Score1=...
> > Score2=
> > ...
> > end;
> > else if gender=="f" then do;
> > Score1=...
> > Score2=
> > ...
> > end;
> >
> > R may not have anything quite like that. R certainly has many other
> > features that SAS lacks.
> >
> > Thanks,
> > Bob
> >
> > =
> > Bob Muenchen (pronounced Min'-chen), Manager
> > Statistical Consulting Center
> > U of TN Office of Information Technology
> > 200 Stokely Management Center, Knoxville, TN 37996-0520
> > Voice: (865) 974-5230
> > FAX: (865) 974-4810
> > Email: [EMAIL PROTECTED]
> > Web: http://oit.utk.edu/scc,
> > News: http://listserv.utk.edu/archives/statnews.html
> > =
> >
> >
> > -Original Message-
> > From: Gabor Grothendieck [mailto:[EMAIL PROTECTED]
> > Sent: Saturday, November 25, 2006 12:39 AM
> > To: Muenchen, Robert A (Bob)
> > Cc: r-help@stat.math.ethz.ch
> > Subject: Re: [R] Multiple Conditional Tranformations
> >
> > And here is a variation:
> >
> > transform(mydata,
> > score1 = (2 + (gender == "m")) * q1 + q2,
> > score2 = score1 + 0.5 * q1
> > )
> >
> > or
> >
> > transform(
> > transform(mydata, score1 = (2 + (gender == "m")) * q1 + q2),
> > score2 = score1 + 0.5 * q1
> > )
> >
> >
> > On 11/25/06, Gabor Grothendieck <[EMAIL PROTECTED]> wrote:
> > > Try this:
> > >
> > >
> > > transform(mydata,
> > > score1 = (2 + (gender == "m")) * q1 + q2,
> > > score2 = (2.5 + (gender == "m")) * q1 + q2
> >
Re: [R] Multiple Conditional Tranformations
Here is a correction:
do.call(rbind, by(mydata, 1:nrow(mydata), function(x)
switch(as.character(x$gender),
m = transform(x, score1 = 3*q1+q2, score2 = 3.5*q1+q2),
f = transform(x, score1 = 2*q1+q2, score2 = 2.5*q1+q2),
transform(x, score1 = NA, score2 = NA))
))
On 11/25/06, Gabor Grothendieck <[EMAIL PROTECTED]> wrote:
> Here are some additional solutions. It appears that the SAS code is
> performing
> the transformation row by row and for each row the code in your post is
> specifying the transformation so if you want to do it that way we
> could use 'by'
> like this (where this time we have also added NA processing for the gender):
>
>
> do.call(rbind, by(mydata, 1:nrow(mydata), function(x)
> switch(as.character(x$gender),
> m = transform(x, score1 = 3*q1+q2, score2 = 3.5*q1+q2),
> f = transform(x, score1 = 2*q1+q2, score2 = 2.5*q1+q2),
> NA)
> ))
>
> # or this somewhat longer version:
>
> do.call(rbind, by(mydata, 1:nrow(mydata), function(x) with(x, {
> if (is.na(gender)) {
> score1 <- score2 <- NA
> } else if (gender == "m") {
> score1 = 3 * q1 + q2
> score2 = 3.5 * q1 + q2
> } else if (gender == "f") {
> score1 = 2 * q1 + q2
> score2 = 2.5 * q1 + q2
> }
> cbind(x, score1, score2)
> })))
>
>
>
>
>
>
>
> On 11/25/06, Muehnchen, Robert A (Bob) <[EMAIL PROTECTED]> wrote:
> > That's exactly what I'm looking for. Thanks so much for taking the time
> > to do it that way.
> >
> > On the redundancy issue, I think SAS checks the "else if" condition only
> > if the original "if" is false. The check for f when not m I put in only
> > to exclude missing values for gender.
> >
> > Thanks!!
> > Bob
> >
> > -Original Message-
> > From: Gabor Grothendieck [mailto:[EMAIL PROTECTED]
> > Sent: Saturday, November 25, 2006 7:37 AM
> > To: Muenchen, Robert A (Bob)
> > Cc: r-help@stat.math.ethz.ch
> > Subject: Re: [R] Multiple Conditional Tranformations
> >
> > Firstly your outline does not check once, it checks twice. First it
> > check for "m" and then it redundantly checks for "f". On the other
> > hand the two variations in my post do check once.
> >
> > Although substantially longer than the solutions in my prior posts,
> > if you want the style shown in your post try this:
> >
> > mydata2 <- cbind(mydata, score1 = 0, score2 = 0)
> > is.m <- mydata$gender == "m"
> >
> > mydata2[is.m, ] <- transform(mydata[is.m, ],
> > score1 = 3 * q1 + q2,
> > score2 = 3.5 * q1 + q2
> > )
> >
> > mydata2[!is.m,] <- transform(mydata2[!is.m, ],
> > score1 = 2 * q1 + q2,
> > score2 = 2.5 * q1 + q2
> > )
> >
> > On 11/25/06, Muenchen, Robert A (Bob) <[EMAIL PROTECTED]> wrote:
> > > Gabor,
> > >
> > > Those are handy variations! Perhaps my brain in still in SAS mode on
> > > this. I'm expecting something like the code below that checks for male
> > > only once, checks for female only when not male (skipping NAs) and
> > does
> > > all formulas under the appropriate conditions. The formulas I made up
> > to
> > > keep the code short & may not be as easily modified to let the logical
> > > 0/1 values fix them.
> > >
> > > if gender=="m" then do;
> > > Score1=...
> > > Score2=
> > > ...
> > > end;
> > > else if gender=="f" then do;
> > > Score1=...
> > > Score2=
> > > ...
> > > end;
> > >
> > > R may not have anything quite like that. R certainly has many other
> > > features that SAS lacks.
> > >
> > > Thanks,
> > > Bob
> > >
> > > =========
> > > Bob Muenchen (pronounced Min'-chen), Manager
> > > Statistical Consulting Center
> > > U of TN Office of Information Technology
> > > 200 Stokely Management Center, Knoxville, TN 37996-0520
> > > Voice: (865) 974-5230
> > > FAX: (865) 974-4810
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> > > =
> > >
> > >
> > > -Original Message-
> > > From: Gabor Grothendieck [mailto:[EMAIL PROTECTED]
> > > Sent: Saturday, Nove
Re: [R] Multiple Conditional Tranformations
I have a program that is similar to your longer version, but I could
never get the syntax quite right. This will be a big help in
understanding how by works with functions.
Thanks,
Bob
-Original Message-
From: Gabor Grothendieck [mailto:[EMAIL PROTECTED]
Sent: Saturday, November 25, 2006 11:11 AM
To: Muenchen, Robert A (Bob)
Cc: r-help@stat.math.ethz.ch
Subject: Re: [R] Multiple Conditional Tranformations
Here is a correction:
do.call(rbind, by(mydata, 1:nrow(mydata), function(x)
switch(as.character(x$gender),
m = transform(x, score1 = 3*q1+q2, score2 = 3.5*q1+q2),
f = transform(x, score1 = 2*q1+q2, score2 = 2.5*q1+q2),
transform(x, score1 = NA, score2 = NA))
))
On 11/25/06, Gabor Grothendieck <[EMAIL PROTECTED]> wrote:
> Here are some additional solutions. It appears that the SAS code is
performing
> the transformation row by row and for each row the code in your post
is
> specifying the transformation so if you want to do it that way we
> could use 'by'
> like this (where this time we have also added NA processing for the
gender):
>
>
> do.call(rbind, by(mydata, 1:nrow(mydata), function(x)
> switch(as.character(x$gender),
> m = transform(x, score1 = 3*q1+q2, score2 = 3.5*q1+q2),
> f = transform(x, score1 = 2*q1+q2, score2 = 2.5*q1+q2),
> NA)
> ))
>
> # or this somewhat longer version:
>
> do.call(rbind, by(mydata, 1:nrow(mydata), function(x) with(x, {
> if (is.na(gender)) {
> score1 <- score2 <- NA
> } else if (gender == "m") {
> score1 = 3 * q1 + q2
> score2 = 3.5 * q1 + q2
> } else if (gender == "f") {
> score1 = 2 * q1 + q2
> score2 = 2.5 * q1 + q2
> }
> cbind(x, score1, score2)
> })))
>
>
>
>
>
>
>
> On 11/25/06, Muehnchen, Robert A (Bob) <[EMAIL PROTECTED]> wrote:
> > That's exactly what I'm looking for. Thanks so much for taking the
time
> > to do it that way.
> >
> > On the redundancy issue, I think SAS checks the "else if" condition
only
> > if the original "if" is false. The check for f when not m I put in
only
> > to exclude missing values for gender.
> >
> > Thanks!!
> > Bob
> >
> > -Original Message-
> > From: Gabor Grothendieck [mailto:[EMAIL PROTECTED]
> > Sent: Saturday, November 25, 2006 7:37 AM
> > To: Muenchen, Robert A (Bob)
> > Cc: r-help@stat.math.ethz.ch
> > Subject: Re: [R] Multiple Conditional Tranformations
> >
> > Firstly your outline does not check once, it checks twice. First it
> > check for "m" and then it redundantly checks for "f". On the other
> > hand the two variations in my post do check once.
> >
> > Although substantially longer than the solutions in my prior posts,
> > if you want the style shown in your post try this:
> >
> > mydata2 <- cbind(mydata, score1 = 0, score2 = 0)
> > is.m <- mydata$gender == "m"
> >
> > mydata2[is.m, ] <- transform(mydata[is.m, ],
> > score1 = 3 * q1 + q2,
> > score2 = 3.5 * q1 + q2
> > )
> >
> > mydata2[!is.m,] <- transform(mydata2[!is.m, ],
> > score1 = 2 * q1 + q2,
> > score2 = 2.5 * q1 + q2
> > )
> >
> > On 11/25/06, Muenchen, Robert A (Bob) <[EMAIL PROTECTED]> wrote:
> > > Gabor,
> > >
> > > Those are handy variations! Perhaps my brain in still in SAS mode
on
> > > this. I'm expecting something like the code below that checks for
male
> > > only once, checks for female only when not male (skipping NAs) and
> > does
> > > all formulas under the appropriate conditions. The formulas I made
up
> > to
> > > keep the code short & may not be as easily modified to let the
logical
> > > 0/1 values fix them.
> > >
> > > if gender=="m" then do;
> > > Score1=...
> > > Score2=
> > > ...
> > > end;
> > > else if gender=="f" then do;
> > > Score1=...
> > > Score2=
> > > ...
> > > end;
> > >
> > > R may not have anything quite like that. R certainly has many
other
> > > features that SAS lacks.
> > >
> > > Thanks,
> > > Bob
> > >
> > > =============
> > > Bob Muenchen (pronounced Min'-chen), Manager
> > > Statistical Consulting Center
> > > U of TN Office of Information Technology
> > > 200 Stokely Management Center, Knoxville, TN 37996-0520
> > > Voice: (865) 974-5230
