R help - Mar 2010 - Adding matrix rows that have the same name?

Does anyone know if there is an R function that will take a matrix like this

jim     1  0  0  0  0  0
jim     0  1  0  0  0  0
jim     0  0  1  0  0  0
bob    1  0  0  0  0  0
bob    0  0  1  0  0  0
harry  0  0  1  0  0  0
harry  0  0  0  1  0  0
harry  0  0  0  0  1  0
harry  0  0  0  0  0  1

and make it like this? (that is, add together rows that have the same name?)

jim    1 1 1 0 0 0
bob   1 0 1 0 0 0
harry 0 0 1 1 1 1


here's the code I started with, if it helps

library (dummies)
a <- c(1,1,1,2,2,3,3,3,3)
b<-
c("A","B","C","A","C","C","D","E","F")
name<- c("jim", "jim", "jim", "bob",
"bob", "harry", "harry", "harry",
"harry")
MyMat <- cbind (a, b)
rownames (MyMat) <- name
dum.mat.temp <- dummy ("b", MyMat)
       #dum.mat.temp <-cbind (name, dum.mat.temp) # if you want names
as a column
dum.mat.temp

Many thanks in advance!
--Sarah

Try this:

aggregate(as.data.frame(dum.mat.temp), list(row.names(dum.mat.temp)), sum)

On Tue, Mar 23, 2010 at 6:15 PM, Sarah Berke <skberke at gmail.com>
wrote:
> Does anyone know if there is an R function that will take a matrix like
this
>
> jim ? ? 1 ?0 ?0 ?0 ?0 ?0
> jim ? ? 0 ?1 ?0 ?0 ?0 ?0
> jim ? ? 0 ?0 ?1 ?0 ?0 ?0
> bob ? ?1 ?0 ?0 ?0 ?0 ?0
> bob ? ?0 ?0 ?1 ?0 ?0 ?0
> harry ?0 ?0 ?1 ?0 ?0 ?0
> harry ?0 ?0 ?0 ?1 ?0 ?0
> harry ?0 ?0 ?0 ?0 ?1 ?0
> harry ?0 ?0 ?0 ?0 ?0 ?1
>
> and make it like this? (that is, add together rows that have the same
name?)
>
> jim ? ?1 1 1 0 0 0
> bob ? 1 0 1 0 0 0
> harry 0 0 1 1 1 1
>
>
> here's the code I started with, if it helps
>
> library (dummies)
> a <- c(1,1,1,2,2,3,3,3,3)
> b<-
c("A","B","C","A","C","C","D","E","F")
> name<- c("jim", "jim", "jim",
"bob", "bob", "harry", "harry",
"harry", "harry")
> MyMat <- cbind (a, b)
> rownames (MyMat) <- name
> dum.mat.temp <- dummy ("b", MyMat)
> ? ? ? #dum.mat.temp <-cbind (name, dum.mat.temp) # if you want names
> as a column
> dum.mat.temp
>
> Many thanks in advance!
> --Sarah
>
> ______________________________________________
> R-help at 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.
>


-- 
Henrique Dallazuanna
Curitiba-Paran?-Brasil
25? 25' 40" S 49? 16' 22" O

Hi:

The plyr solution is as follows, where your 'matrix' is a data frame m
whose
first column is a factor:
> m
     V1 V2 V3 V4 V5 V6 V7
1   jim  1  0  0  0  0  0
2   jim  0  1  0  0  0  0
3   jim  0  0  1  0  0  0
4   bob  1  0  0  0  0  0
5   bob  0  0  1  0  0  0
6 harry  0  0  1  0  0  0
7 harry  0  0  0  1  0  0
8 harry  0  0  0  0  1  0
9 harry  0  0  0  0  0  1
> str(m)
'data.frame':   9 obs. of  7 variables:
 $ V1: Factor w/ 3 levels "bob","harry",..: 3 3 3 1 1 2 2 2
2
 $ V2: int  1 0 0 1 0 0 0 0 0
<V3 through V7 are also numeric>

library(plyr)
ddply(m, "V1", numcolwise(sum))
     V1 V2 V3 V4 V5 V6 V7
1   bob  1  0  1  0  0  0
2 harry  0  0  1  1  1  1
3   jim  1  1  1  0  0  0

ddply() takes a data frame as input and outputs a data frame. "V1"
specifies
the (categorical) variable over which reductions are desired, and
numcolwise(fun)
applies the function supplied as its argument to all numeric columns.

HTH,
Dennis

On Tue, Mar 23, 2010 at 2:15 PM, Sarah Berke <skberke@gmail.com> wrote:
> Does anyone know if there is an R function that will take a matrix like
> this
>
> jim     1  0  0  0  0  0
> jim     0  1  0  0  0  0
> jim     0  0  1  0  0  0
> bob    1  0  0  0  0  0
> bob    0  0  1  0  0  0
> harry  0  0  1  0  0  0
> harry  0  0  0  1  0  0
> harry  0  0  0  0  1  0
> harry  0  0  0  0  0  1
>
> and make it like this? (that is, add together rows that have the same
> name?)
>
> jim    1 1 1 0 0 0
> bob   1 0 1 0 0 0
> harry 0 0 1 1 1 1
>
>
> here's the code I started with, if it helps
>
> library (dummies)
> a <- c(1,1,1,2,2,3,3,3,3)
> b<-
c("A","B","C","A","C","C","D","E","F")
> name<- c("jim", "jim", "jim",
"bob", "bob", "harry", "harry",
"harry",
> "harry")
> MyMat <- cbind (a, b)
> rownames (MyMat) <- name
> dum.mat.temp <- dummy ("b", MyMat)
>       #dum.mat.temp <-cbind (name, dum.mat.temp) # if you want names
> as a column
> dum.mat.temp
>
> Many thanks in advance!
> --Sarah
>
> ______________________________________________
> 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.
>
	[[alternative HTML version deleted]]