[R] Substitution of Variables

[(Ted Harding)]

On 02-Jul-07 23:01:07, Judith Flores wrote:
> Hi,
>    I need to run a script under the variable (that
> comes from a csv file) that is assigned to another
> variable. This is very a simplified version of what I
> want to do:
> 
> data<-read.csv('name.csv')
> names(data)<-("VA","VB","VC")
> 
> v<-VA
> 
> mn(v)
> 
> Thank you in advance,
> Judith

read.csv() makes 'data' into a dataframe. This is essentially
a list with named components. So VA is not yet available as
a variable in your program. The data for the variable you want
to call "VA" is stored as the component 'data$VA' of 'data'.
The names "VA", "VB", "VC" are the names you have given to
the *components* of 'data'; you have not created separate
variables with these names.

So you can assign the data for VA directly to 'v' with:

  v<-data$VA

or (if you think you will need it later) create a variable VA
using

  VA<-data$VA

and, if you want a variable called 'v' as well, then:

  v<-VA

Hoping this helps,
Ted.

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Date: 03-Jul-07                                       Time: 00:32:40
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