Skip to content
Back to formatted view

Raw Message

Message-ID: <1359260822.50164.YahooMailNeo@web142602.mail.bf1.yahoo.com>
Date: 2013-01-27T04:27:02Z
From: arun
Subject: Converting column of strings to boolean
In-Reply-To: <1359242865874-4656741.post@n4.nabble.com>

Hi,

Anther possibility may be to use:

library(MatrixModels)

? model.Matrix(~d-1,sparse=FALSE)
#7 x 4 Matrix of class "ddenseModelMatrix"
?# dblue dgreen dred dyellow
#1 ??? 0????? 0??? 1?????? 0
#2???? 0????? 1??? 0?????? 0
#3???? 0????? 0??? 1?????? 0
#4???? 1????? 0??? 0?????? 0
#5???? 0????? 1??? 0?????? 0
#6???? 0????? 0??? 0?????? 1
#7???? 0????? 0??? 1?????? 0
?model.Matrix(~d-1,sparse=TRUE)
#"dsparseModelMatrix": 7 x 4 sparse Matrix of class "dgCMatrix"
?# dblue dgreen dred dyellow
#1???? .????? .??? 1?????? .
#2???? .????? 1??? .?????? .
#3???? .????? .??? 1?????? .
#4???? 1????? .??? .?????? .
#5???? .????? 1??? .?????? .
#6???? .????? .??? .?????? 1
#7???? .????? .??? 1?????? .
#@ assign:? 1 1 1 1 
#@ contrasts:
#$d
#[1] "contr.treatment"

A.K.


----- Original Message -----
From: Pete Brecknock <Peter.Brecknock at bp.com>
To: r-help at r-project.org
Cc: 
Sent: Saturday, January 26, 2013 6:27 PM
Subject: Re: [R] Converting column of strings to boolean

domcastro wrote
> Hi
> 
> I'm trying to convert a column of strings (nominal types) to a set of
> boolean / binary / logical values. For example, in the column there is
> red, blue, green and yellow. There are 100 rows and each has a colour. I
> want to convert the column to 4 columns: red, blue, green,yellow and then
> either 1 or 0 put in the relevant row.
> Thanks

maybe model.matrix will help ....

# d is my understanding of your data
d<-factor(c("red","green","red","blue","green","yellow","red"))
model.matrix(~d -1)

HTH 

Pete



--
View this message in context: http://r.789695.n4.nabble.com/Converting-column-of-strings-to-boolean-tp4656739p4656741.html
Sent from the R help mailing list archive at Nabble.com.

______________________________________________
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.