R help - Oct 2003 - Generating Data Sets -- Each with a Different Name

Hello all.

I was wondering if anyone had insight into how I might generate a large 
number of data sets/vectors, where each of the data sets/vectors have a 
different name?

For example, suppose I wanted to generate N data sets/vectors, each with a 
different name such as:

Random.Data.1 <- rnorm(10, 0, 1)
Random.Data.2 <- rnorm(10, 0, 1)
Random.Data.3 <- rnorm(10, 0, 1)
	.		.	
	.		.
	.		.
Random.Data.N <- rnorm(10, 0, 1)

Because I don't want to name each data set/vector myself, I want some sort 
of looping/automatic procedure to do it for me. However, I'm not sure how 
to do this.

What I want is something conceptually analogous to the following:

for(i in 1:N)
{
Random.Data.i <- rnorm(10, 0, 1)
}

Note the "i" in the "Random.Data.i" vector. This is the
value I want to
change for each iteration of the loop, so that I can have N data 
sets/vectors automatically generated for me with different names.

Does anyone know of a method where I can accomplish such a procedure.
Thanks for your thoughts,
Ken

P.S. For those of you wondering why I would ever want to do such a thing, 
it is because I need a large number of data sets to use in a Monte Carlo 
study with specialized software. If I could do the simulation all is R, 
then obviously I could loop the whole procedure. The program I am using has 
a limited Monte Carlo facility where each of the (say 10,000) data sets 
must be generated elsewhere.

Have you considered using "paste(..., sep="") to generate either 
the object names or file names you want? 

      If you want objects in R, have you considered "assign"?  If you 
want files, then have you considered "write"? 

      hope this helps. 
      spencer graves

Ken Kelley wrote:
> Hello all.
>
> I was wondering if anyone had insight into how I might generate a 
> large number of data sets/vectors, where each of the data sets/vectors 
> have a different name?
>
> For example, suppose I wanted to generate N data sets/vectors, each 
> with a different name such as:
>
> Random.Data.1 <- rnorm(10, 0, 1)
> Random.Data.2 <- rnorm(10, 0, 1)
> Random.Data.3 <- rnorm(10, 0, 1)
>     .        .   
>     .        .
>     .        .
> Random.Data.N <- rnorm(10, 0, 1)
>
> Because I don't want to name each data set/vector myself, I want some 
> sort of looping/automatic procedure to do it for me. However, I'm not 
> sure how to do this.
>
> What I want is something conceptually analogous to the following:
>
> for(i in 1:N)
> {
> Random.Data.i <- rnorm(10, 0, 1)
> }
>
> Note the "i" in the "Random.Data.i" vector. This is the
value I want
> to change for each iteration of the loop, so that I can have N data 
> sets/vectors automatically generated for me with different names.
>
> Does anyone know of a method where I can accomplish such a procedure.
> Thanks for your thoughts,
> Ken
>
> P.S. For those of you wondering why I would ever want to do such a 
> thing, it is because I need a large number of data sets to use in a 
> Monte Carlo study with specialized software. If I could do the 
> simulation all is R, then obviously I could loop the whole procedure. 
> The program I am using has a limited Monte Carlo facility where each 
> of the (say 10,000) data sets must be generated elsewhere.
>
> ______________________________________________
> R-help at stat.math.ethz.ch mailing list
> https://www.stat.math.ethz.ch/mailman/listinfo/r-help

You need paste and assign functions.  Paste will create a sequence of names
and assign will give values to the variables with these names.

This modification of your loop should work

for(i in 1:N)
{
assign(paste("Random.Data.", i, sep=''), rnorm(10, 0, 1))
}

Cheers,

Andy

__________________________________
Andy Jaworski
Engineering Systems Technology Center
3M Center, 518-1-01
St. Paul, MN 55144-1000
-----
E-mail: apjaworski at mmm.com
Tel:  (651) 733-6092
Fax:  (651) 736-3122


|---------+-------------------------------->
|         |           Ken Kelley           |
|         |           <KKelley at nd.edu>     |
|         |           Sent by:             |
|         |           r-help-bounces at stat.m|
|         |           ath.ethz.ch          |
|         |                                |
|         |                                |
|         |           10/23/2003 17:09     |
|         |                                |
|---------+-------------------------------->
 
>-----------------------------------------------------------------------------------------------------------------------------|
  |                                                                             
|
  |      To:       r-help at stat.math.ethz.ch                                  
|
  |      cc:                                                                    
|
  |      Subject:  [R] Generating Data Sets -- Each with a Different Name       
|
 
>-----------------------------------------------------------------------------------------------------------------------------|




Hello all.

I was wondering if anyone had insight into how I might generate a large
number of data sets/vectors, where each of the data sets/vectors have a
different name?

For example, suppose I wanted to generate N data sets/vectors, each with a
different name such as:

Random.Data.1 <- rnorm(10, 0, 1)
Random.Data.2 <- rnorm(10, 0, 1)
Random.Data.3 <- rnorm(10, 0, 1)
             .                       .
             .                       .
             .                       .
Random.Data.N <- rnorm(10, 0, 1)

Because I don't want to name each data set/vector myself, I want some sort
of looping/automatic procedure to do it for me. However, I'm not sure how
to do this.

What I want is something conceptually analogous to the following:

for(i in 1:N)
{
Random.Data.i <- rnorm(10, 0, 1)
}

Note the "i" in the "Random.Data.i" vector. This is the
value I want to
change for each iteration of the loop, so that I can have N data
sets/vectors automatically generated for me with different names.

Does anyone know of a method where I can accomplish such a procedure.
Thanks for your thoughts,
Ken

P.S. For those of you wondering why I would ever want to do such a thing,
it is because I need a large number of data sets to use in a Monte Carlo
study with specialized software. If I could do the simulation all is R,
then obviously I could loop the whole procedure. The program I am using has

a limited Monte Carlo facility where each of the (say 10,000) data sets
must be generated elsewhere.

______________________________________________
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https://www.stat.math.ethz.ch/mailman/listinfo/r-help