R help - Apr 2009 - How to apply a function to all combinations of the values of 2 or more variables?

Hi, All 

Forgive me if this is a stupid newbie question. I'm having no luck
googling an answer to this, probably because I don't know the right R
terminology to frame my question. I want to know how to run an R
function on each combination of the values of 2 or more variables. In
SAS-speak this is multiple "BY variables" or "CLASS
variables".

In R I've figured out how to do what I want with one by value. 

by(mf,mf$centre,summary)

Centre is one of the columns in the data frame "mf" which looks like
this:

names(mf)
[1] "centre"   "complex"  "appl"    
"pool"     "month"    "alloc_gb"

I'd like to analyze, for example, by complex within centre. This has a
manageable number of combinations:

table(mf$centre,mf$complex)
      
                   A      B      C      D      E      F      G      H
I      J      K      L
  B         0      0      0      0      0      0      0      0      0
0      0  60574      0
  G        44    209      0  94613      0    156      0   2541      0
748      0      0 215511
  O         0      0      0      0      0      0   3446      0    676
0  84400      0      0
  Q         0      0    298      0  66277      0      0      0      0
0      0      0      0

In SAS what I'm after is something like:

Proc summary nway;
 class centre complex;
 var alloc_gb;
 output out=s sum=; 
 run;

How do I get something similar in R?

Jim Lane
Capacity Planner
RBC Financial Group
315 Front St W
6th Floor - H14
Toronto, Ontario CANADA
M5V 3A4
416-348-6024

Display of superior knowledge is as great a vulgarity
as display of superior wealth - greater indeed, inasmuch 
as knowledge should tend more definitely than wealth
towards discretion and good manners.

- H. W. Fowler, Modern English Usage


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	[[alternative HTML version deleted]]

I think you want to have a look at the plyr or doBy packages.

It would be easier to give a precise answer with a minimal example.

HTH,

baptiste

On 15 Apr 2009, at 18:03, Lane, Jim wrote:
> Hi, All
>
> Forgive me if this is a stupid newbie question. I'm having no luck
> googling an answer to this, probably because I don't know the right R
> terminology to frame my question. I want to know how to run an R
> function on each combination of the values of 2 or more variables. In
> SAS-speak this is multiple "BY variables" or "CLASS
variables".
>
> In R I've figured out how to do what I want with one by value.
>
> by(mf,mf$centre,summary)
>
> Centre is one of the columns in the data frame "mf" which looks
like
> this:
>
> names(mf)
> [1] "centre"   "complex"  "appl"    
"pool"     "month"    "alloc_gb"
>
> I'd like to analyze, for example, by complex within centre. This has a
> manageable number of combinations:
>
> table(mf$centre,mf$complex)
>
>                   A      B      C      D      E      F      G      H
> I      J      K      L
>  B         0      0      0      0      0      0      0      0      0
> 0      0  60574      0
>  G        44    209      0  94613      0    156      0   2541      0
> 748      0      0 215511
>  O         0      0      0      0      0      0   3446      0    676
> 0  84400      0      0
>  Q         0      0    298      0  66277      0      0      0      0
> 0      0      0      0
>
> In SAS what I'm after is something like:
>
> Proc summary nway;
> class centre complex;
> var alloc_gb;
> output out=s sum=;
> run;
>
> How do I get something similar in R?
>
> Jim Lane
> Capacity Planner
> RBC Financial Group
> 315 Front St W
> 6th Floor - H14
> Toronto, Ontario CANADA
> M5V 3A4
> 416-348-6024
>
> Display of superior knowledge is as great a vulgarity
> as display of superior wealth - greater indeed, inasmuch
> as knowledge should tend more definitely than wealth
> towards discretion and good manners.
>
> - H. W. Fowler, Modern English Usage
>
>
> _______________________________________________________________________
>
> This e-mail may be privileged and/or confidential, and the sender  
> does not waive any related rights and obligations.
> Any distribution, use or copying of this e-mail or the information  
> it contains by other than an intended recipient is unauthorized.
> If you received this e-mail in error, please advise me (by return e- 
> mail or otherwise) immediately.
>
> Ce courrier ?lectronique est confidentiel et prot?g?. L'exp?diteur  
> ne renonce pas aux droits et obligations qui s'y rapportent.
> Toute diffusion, utilisation ou copie de ce message ou des  
> renseignements qu'il contient par une personne autre que le (les)  
> destinataire(s) d?sign?(s) est interdite.
> Si vous recevez ce courrier ?lectronique par erreur, veuillez m'en  
> aviser imm?diatement, par retour de courrier ?lectronique ou par un  
> autre moyen.
>
> 	[[alternative HTML version deleted]]
>
> <ATT00001.txt>
_____________________________

Baptiste Augui?

School of Physics
University of Exeter
Stocker Road,
Exeter, Devon,
EX4 4QL, UK

Phone: +44 1392 264187

http://newton.ex.ac.uk/research/emag

Check out plyr:

http://had.co.nz/plyr/

On Wed, Apr 15, 2009 at 2:03 PM, Lane, Jim <jim.lane at rbc.com>
wrote:
> Hi, All
>
> Forgive me if this is a stupid newbie question. I'm having no luck
> googling an answer to this, probably because I don't know the right R
> terminology to frame my question. I want to know how to run an R
> function on each combination of the values of 2 or more variables. In
> SAS-speak this is multiple "BY variables" or "CLASS
variables".
>
> In R I've figured out how to do what I want with one by value.
>
> by(mf,mf$centre,summary)
>
> Centre is one of the columns in the data frame "mf" which looks
like
> this:
>
> names(mf)
> [1] "centre" ? "complex" ?"appl" ? ?
"pool" ? ? "month" ? ?"alloc_gb"
>
> I'd like to analyze, for example, by complex within centre. This has a
> manageable number of combinations:
>
> table(mf$centre,mf$complex)
>
> ? ? ? ? ? ? ? ? ? A ? ? ?B ? ? ?C ? ? ?D ? ? ?E ? ? ?F ? ? ?G ? ? ?H
> I ? ? ?J ? ? ?K ? ? ?L
> ?B ? ? ? ? 0 ? ? ?0 ? ? ?0 ? ? ?0 ? ? ?0 ? ? ?0 ? ? ?0 ? ? ?0 ? ? ?0
> 0 ? ? ?0 ?60574 ? ? ?0
> ?G ? ? ? ?44 ? ?209 ? ? ?0 ?94613 ? ? ?0 ? ?156 ? ? ?0 ? 2541 ? ? ?0
> 748 ? ? ?0 ? ? ?0 215511
> ?O ? ? ? ? 0 ? ? ?0 ? ? ?0 ? ? ?0 ? ? ?0 ? ? ?0 ? 3446 ? ? ?0 ? ?676
> 0 ?84400 ? ? ?0 ? ? ?0
> ?Q ? ? ? ? 0 ? ? ?0 ? ?298 ? ? ?0 ?66277 ? ? ?0 ? ? ?0 ? ? ?0 ? ? ?0
> 0 ? ? ?0 ? ? ?0 ? ? ?0
>
> In SAS what I'm after is something like:
>
> Proc summary nway;
> ?class centre complex;
> ?var alloc_gb;
> ?output out=s sum=;
> ?run;
>
> How do I get something similar in R?
>
> Jim Lane
> Capacity Planner
> RBC Financial Group
> 315 Front St W
> 6th Floor - H14
> Toronto, Ontario CANADA
> M5V 3A4
> 416-348-6024
>
> Display of superior knowledge is as great a vulgarity
> as display of superior wealth - greater indeed, inasmuch
> as knowledge should tend more definitely than wealth
> towards discretion and good manners.
>
> - H. W. Fowler, Modern English Usage
>
>
> _______________________________________________________________________
>
> This e-mail may be privileged and/or confidential, and the sender does not
waive any related rights and obligations.
> Any distribution, use or copying of this e-mail or the information it
contains by other than an intended recipient is unauthorized.
> If you received this e-mail in error, please advise me (by return e-mail or
otherwise) immediately.
>
> Ce courrier ?lectronique est confidentiel et prot?g?. L'exp?diteur ne
renonce pas aux droits et obligations qui s'y rapportent.
> Toute diffusion, utilisation ou copie de ce message ou des renseignements
qu'il contient par une personne autre que le (les) destinataire(s)
d?sign?(s) est interdite.
> Si vous recevez ce courrier ?lectronique par erreur, veuillez m'en
aviser imm?diatement, par retour de courrier ?lectronique ou par un autre moyen.
>
> ? ? ? ?[[alternative HTML version deleted]]
>
>
> ______________________________________________
> R-help at r-project.org 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.
>
>


-- 
Mike Lawrence
Graduate Student
Department of Psychology
Dalhousie University

Looking to arrange a meeting? Check my public calendar:
http://tr.im/mikes_public_calendar

~ Certainty is folly... I think. ~

Phil: thank you very much, that's exactly what I was looking for! Why I
couldn't have figured that out from the doc for myself is another
question:-)

-Jim

-----Original Message-----
From: Phil Spector [mailto:spector at stat.berkeley.edu] 
Sent: 2009, April, 15 1:21 PM
To: Lane, Jim
Subject: Re: [R] How to apply a function to all combinations of the
values of 2 or more variables?

by(mf,list(mf$centre,mf$complex),summary)

                                        - Phil Spector
 					 Statistical Computing Facility
 					 Department of Statistics
 					 UC Berkeley
 					 spector at stat.berkeley.edu


On Wed, 15 Apr 2009, Lane, Jim wrote:
> Hi, All
>
> Forgive me if this is a stupid newbie question. I'm having no luck 
> googling an answer to this, probably because I don't know the right R 
> terminology to frame my question. I want to know how to run an R 
> function on each combination of the values of 2 or more variables. In 
> SAS-speak this is multiple "BY variables" or "CLASS
variables".
>
> In R I've figured out how to do what I want with one by value.
>
> by(mf,mf$centre,summary)
>
> Centre is one of the columns in the data frame "mf" which looks
like
> this:
>
> names(mf)
> [1] "centre"   "complex"  "appl"    
"pool"     "month"    "alloc_gb"
>
> I'd like to analyze, for example, by complex within centre. This has a
> manageable number of combinations:
>
> table(mf$centre,mf$complex)
>
>                   A      B      C      D      E      F      G      H
> I      J      K      L
>  B         0      0      0      0      0      0      0      0      0
> 0      0  60574      0
>  G        44    209      0  94613      0    156      0   2541      0
> 748      0      0 215511
>  O         0      0      0      0      0      0   3446      0    676
> 0  84400      0      0
>  Q         0      0    298      0  66277      0      0      0      0
> 0      0      0      0
>
> In SAS what I'm after is something like:
>
> Proc summary nway;
> class centre complex;
> var alloc_gb;
> output out=s sum=;
> run;
>
> How do I get something similar in R?
>
> Jim Lane
> Capacity Planner
> RBC Financial Group
> 315 Front St W
> 6th Floor - H14
> Toronto, Ontario CANADA
> M5V 3A4
> 416-348-6024
>
> Display of superior knowledge is as great a vulgarity as display of 
> superior wealth - greater indeed, inasmuch as knowledge should tend 
> more definitely than wealth towards discretion and good manners.
>
> - H. W. Fowler, Modern English Usage
>
>
> ______________________________________________________________________
> _
>
> This e-mail may be privileged and/or confidential, and the sender does
not waive any related rights and obligations.
> Any distribution, use or copying of this e-mail or the information it
contains by other than an intended recipient is
unauthorized.
> If you received this e-mail in error, please advise me (by return
e-mail or otherwise) immediately.
>
> Ce courrier ??ectronique est confidentiel et prot???? L'exp??iteur ne
renonce pas aux droits et obligations qui s'y
rapportent.
> Toute diffusion, utilisation ou copie de ce message ou des
renseignements qu'il contient par une personne autre que le (les)
destinataire(s) d??ign??s) est interdite.
> Si vous recevez ce courrier ??ectronique par erreur, veuillez m'en
aviser imm??iatement, par retour de courrier ??ectronique ou par un
autre moyen.
>
> 	[[alternative HTML version deleted]]
>
>
_______________________________________________________________________

This e-mail may be privileged and/or confidential, and the sender does not waive
any related rights and obligations.
Any distribution, use or copying of this e-mail or the information it contains
by other than an intended recipient is unauthorized.
If you received this e-mail in error, please advise me (by return e-mail or
otherwise) immediately.

Ce courrier ?lectronique est confidentiel et prot?g?. L'exp?diteur ne
renonce pas aux droits et obligations qui s'y rapportent.
Toute diffusion, utilisation ou copie de ce message ou des renseignements
qu'il contient par une personne autre que le (les) destinataire(s)
d?sign?(s) est interdite.
Si vous recevez ce courrier ?lectronique par erreur, veuillez m'en aviser
imm?diatement, par retour de courrier ?lectronique ou par un autre moyen.