R help - May 2009 - Input to variables - help please

Dear list

I have managed to write a short program to evaluate data which is inputted
from a csv file using the following

x = read.csv("wms_results.csv", header=TRUE)

All works fine but since I have a number of similar data files which have
different names, I would like the program to allow me to input the file
name, rather than having to edit the program.
>From the documentation I am unclear how to replace the
"filename.csv" with a
string varaiable so that from the keyboard I can input the name.

Also which command can I use to output some text to the monitor as a prompt

Any help would be great and apologies for such a simple question. Thanks

Regards
Steve

Steve Sidney wrote:
> Dear list
>
> I have managed to write a short program to evaluate data which is 
> inputted
> from a csv file using the following
>
> x = read.csv("wms_results.csv", header=TRUE)
>
> All works fine but since I have a number of similar data files which have
> different names, I would like the program to allow me to input the file
> name, rather than having to edit the program.
>
>> From the documentation I am unclear how to replace the
"filename.csv"
>> with a
> string varaiable so that from the keyboard I can input the name.
>
> Also which command can I use to output some text to the monitor as a 
> prompt
>
> Any help would be great and apologies for such a simple question. Thanks
>
> Regards
> Steve
>
> ______________________________________________
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> PLEASE do read the posting guide 
> http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.
Hi Steve,

I suspect the choose.files() function could be useful in this setting. 
Also, I've read on this forum that message() or cat() were commonly used 
for a prompt (all taken from Prof. Brian Ripley's reply to "Prompt
comes
too late").

Hope this helps,

-- 
*Luc Villandr?*
/Biostatistician
McGill University Health Center -
Montreal Children's Hospital Research Institute/

On 13-May-09 19:49:35, Steve Sidney wrote:
> Dear list
> I have managed to write a short program to evaluate data which is
> inputted from a csv file using the following
> 
> x = read.csv("wms_results.csv", header=TRUE)
> 
> All works fine but since I have a number of similar data files which
> have different names, I would like the program to allow me to input
> the file name, rather than having to edit the program.
> 
> From the documentation I am unclear how to replace the
"filename.csv"
> with a string varaiable so that from the keyboard I can input the name.
> 
> Also which command can I use to output some text to the monitor as a
> prompt
> 
> Any help would be great and apologies for such a simple question.
> Thanks
> 
> Regards
> Steve
Try:

  NextFile <- readline("Enter the CSV filename:\n")
  x = read.csv(NextFile, header=TRUE)

You will then get a prompt "Enter the CSV filename:"
so enter it. Then it will read it.

Example (from the terminal):

  > NextFile <- readline("Enter the CSV filename:\n")
  Enter the CSV filename:
  ACBDEFG.csv
  > NextFile
  [1] "ACBDEFG.csv"
  >

Ted.

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E-Mail: (Ted Harding) <Ted.Harding at manchester.ac.uk>
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Date: 13-May-09                                       Time: 21:12:19
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