[R] Subset of Data

[arun]

Hi Farnoosh,
Try this:
set.seed(151)
mat1<-matrix(sample(1:400,100,replace=TRUE),ncol=20)
set.seed(15)
colnames(mat1)<-paste(sample(c("proc","Lab","other"),20,replace=TRUE),sample(1:45,20,replace=FALSE),sep="")
mat1[,grepl("proc|Lab",colnames(mat1))]
#     Lab37 proc35 Lab3 Lab24 proc6 proc36 Lab9 Lab17 Lab32 proc34
#[1,]   192    246  241   126   374    122  281   116   215      4
#[2,]   347    182  237   393   300     49  125    90   245    148
#[3,]   312    329  144   285   224    110  378   329   275     79
#[4,]   216    139  300   230   249    206  231   357   188     87
#[5,]   177    383  102   211    26    283   20   351   392    286

#if you want columns not "Lab" or "proc"

mat1[,!grepl("proc|Lab",colnames(mat1))]

A.K.


________________________________
From: farnoosh sheikhi <farnoosh_81 at yahoo.com>
To: "smartpink111 at yahoo.com" <smartpink111 at yahoo.com> 
Cc: "r-help at R-project.org" <r-help at R-project.org> 
Sent: Wednesday, December 12, 2012 3:39 PM
Subject: Subset of Data


Hi Arun,

I have a question about choosing a subset of data.
I have a matrix of 5000 in 3500.
I want to choose specific variables such as proc1 to proc1000 and Lab1 to Lab1600 and put it into a new matrix to run some correlation analysis.
Since I have 3500 variables, I don't know from what column my lab or procedures start.
I really appreciate your help.
Thanks.


Best,Farnoosh Sheikhi