Problem in executing R-script

[Suhaila Haji Mohd Hussin]

Hello. I'm a newbie here.
In my script (I name it readData.R), I wrote the followings:
readData <-function(){ med = read.csv("medicalData.csv");}
Then I tested the script by 'Source R Code' then on the command I typed 'readData()' then I typed 'med' to check if the variable contains the medical data but it returned 'Object med is not found'. What did I do wrong? Please help.
Cheers,Suhaila    
        [[alternative HTML version deleted]]

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[Sarah Goslee]

Hi Suhaila,

You don't need to make a function: your script should just contain:
med <- read.csv("medicalData.csv")

If you do want to make a function, then you need to assign the
resulting value to something, eg:

med <- readData()

but there's no reason to do that. Values that are assigned within a
function don't persist in the global environment.

Sarah

On Mon, May 7, 2012 at 1:41 PM, Suhaila Haji Mohd Hussin
<[hidden email]> wrote:
>
> Hello. I'm a newbie here.
> In my script (I name it readData.R), I wrote the followings:
> readData <-function(){  med = read.csv("medicalData.csv");}
> Then I tested the script by 'Source R Code' then on the command I typed 'readData()' then I typed 'med' to check if the variable contains the medical data but it returned 'Object med is not found'. What did I do wrong? Please help.
> Cheers,Suhaila

--
Sarah Goslee
http://www.functionaldiversity.org

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[hidden email] mailing list
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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.

[Michael Weylandt]

R is a functional language so, by default, assignments (and other
things) within function scope doesn't have global effects. This is
generally considered a _very good thing_ in language design. You'd
perhaps prefer something like:

readData <- function() {
    read.csv("medialData.csv")
}

med <- readData()

which will have the desired outcome.

On Mon, May 7, 2012 at 1:41 PM, Suhaila Haji Mohd Hussin
<[hidden email]> wrote:

>
> Hello. I'm a newbie here.
> In my script (I name it readData.R), I wrote the followings:
> readData <-function(){  med = read.csv("medicalData.csv");}
> Then I tested the script by 'Source R Code' then on the command I typed 'readData()' then I typed 'med' to check if the variable contains the medical data but it returned 'Object med is not found'. What did I do wrong? Please help.
> Cheers,Suhaila
>        [[alternative HTML version deleted]]
>
> ______________________________________________
> [hidden email] mailing list
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.

______________________________________________
[hidden email] mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.

[Berend Hasselman]

On 07-05-2012, at 19:41, Suhaila Haji Mohd Hussin wrote:

>
> Hello. I'm a newbie here.
> In my script (I name it readData.R), I wrote the followings:
> readData <-function(){ med = read.csv("medicalData.csv");}
> Then I tested the script by 'Source R Code' then on the command I typed 'readData()' then I typed 'med' to check if the variable contains the medical data but it returned 'Object med is not found'. What did I do wrong? Please help.

Have a look at section 10.5 "Assignment within functions" of the "An Introduction to R " manual.

Berend

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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.

[Suhaila Haji Mohd Hussin]

Thank Sarah!

> Date: Mon, 7 May 2012 14:06:31 -0400
> Subject: Re: [R] Problem in executing R-script
> From: [hidden email]
> To: [hidden email]
> CC: [hidden email]
>
> Hi Suhaila,
>
> You don't need to make a function: your script should just contain:
> med <- read.csv("medicalData.csv")
>
> If you do want to make a function, then you need to assign the
> resulting value to something, eg:
>
> med <- readData()
>
> but there's no reason to do that. Values that are assigned within a
> function don't persist in the global environment.
>
> Sarah
>
> On Mon, May 7, 2012 at 1:41 PM, Suhaila Haji Mohd Hussin
> <[hidden email]> wrote:
> >
> > Hello. I'm a newbie here.
> > In my script (I name it readData.R), I wrote the followings:
> > readData <-function(){  med = read.csv("medicalData.csv");}
> > Then I tested the script by 'Source R Code' then on the command I typed 'readData()' then I typed 'med' to check if the variable contains the medical data but it returned 'Object med is not found'. What did I do wrong? Please help.
> > Cheers,Suhaila
>
> --
> Sarah Goslee
> http://www.functionaldiversity.org

     
        [[alternative HTML version deleted]]

______________________________________________
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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.