Look at the help files for matrix and rep
?matrix
?rep
## Read dataset
c83 <- read.table('c:\\bin.txt', header = T)
## Create matrix x
x <- matrix( data = 0, ## fill with zeros
nrow = sum( c83$total), ## number of rows
## equal to the sum
## of the c83$total vector
ncol = 4) ## 4 columns
## Create 2 vectors of zeros with length
## equal to the sum of the 'total' variable
## from the c83 dataset and assign to y and g
y <- rep( 0, times = sum(c83$total))
g <- rep( 0, times = sum(c83$total))
## Assign 0 to k
k <- 0
--Matt
> -----Original Message-----
> From: s-news-owner@lists.biostat.wustl.edu
> [mailto:s-news-owner@lists.biostat.wustl.edu]On Behalf Of Terrence
> Murphy
> Sent: Tuesday, November 29, 2005 11:46 AM
> To: s-news@lists.biostat.wustl.edu
> Subject: [S] help interpret a line of code
>
>
> Dear Users,
>
> I'm new to Splus and pardon this question, but don't understand the
> following lines in a program
> I'm trying to use:
>
> c83<-read.table('c:\\bin.txt',header=T)
> x<-matrix(0,sum(c83$total),4)
> y<-rep(0,sum(c83$total))
> g<-rep(0,sum(c83$total))
> k<-0
>
> The first line reads data from a text file into a vector
> called c83. The
> second line establishes a
> matrix x but with what? What is the value of c83$total ?
> What do the three
> terms 0, c83$total and 4 stand for with regard to the dimensions and
> contents of the matrix x?
>
> I assume the last three lines set up vectors of 0 with
> respective lengths
> of c83$total , c83$total , and 0, no ?
>
> Any help greatly appreciated.
>
>
> Terrence E. Murphy, Ph.D.
> Program on Aging
> Yale University
> 1 Church St., 7th Floor
> New Haven, CT 06437
> terrence.murphy@yale.edu
> phone: 203-764-9805
> fax: 203-764-9831
>
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