R help - Nov 2012 - Newbie question : selecting subset of a Matrix

I have a matrix, I would like to use it like I use where query on an SQL table

Let's say my matrix is
> wok
    who  task
1   joe task1
2   joe task2
3   joe task3
4  jack task1
5  jack task2

I want to extract a matrix that contains only rows where
    who = "joe" and task != "task2"

The result would be the following matrix

1   joe task1
2   joe task3

How can I do that with R ?

Hi,
Try this:
wok<-read.table(text="
? who? task
? joe task1
? joe task2
? joe task3
? jack task1
? jack task2
",sep="",header=TRUE,stringsAsFactors=FALSE)


wok2<- wok[wok[,1]=="joe" & wok[,2]!="task2",]
wok2

#? who? task
#1 joe task1
#3 joe task3
A.K.




----- Original Message -----
From: "thocar at free.fr" <thocar at free.fr>
To: r-help at r-project.org
Cc: 
Sent: Wednesday, November 7, 2012 5:20 PM
Subject: [R] Newbie question : selecting subset of a Matrix

I have a matrix, I would like to use it like I use where query on an SQL table

Let's say my matrix is
> wok
? ? who? task
1?  joe task1
2?  joe task2
3?  joe task3
4? jack task1
5? jack task2

I want to extract a matrix that contains only rows where
? ? who = "joe" and task != "task2"

The result would be the following matrix

1?  joe task1
2?  joe task3

How can I do that with R ?

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