[R] understanding the FUNCTION function

[Wet Bell Diver]

In addition: the object MyNumberIs *is* created, but inside the 
environment "attached" to the function as you evaluate it. And this 
environment is gone when the function is done. (there is more to it, but 
this is basically how it works). This is what Michael refers to in his 
answer.
So, when you look for MyNumberIs in the global environment, it is not 
there, since it was never created there, nor was it copied to it.
If you were adamant about finding it there, you could change the 
function into

Number <-  function(x) {MyNumberIs <<- x}

which would work in your example. Note, however, that this is almost 
always ill-advised.
See ?"<<-"

--Peter



Op 25-4-2012 23:07, R. Michael Weylandt <michael.weylandt at gmail.com> 
schreef:
> Functions are not subroutines; that is, the effects (including assignments) are not global.
>
> You need something like
>
> F<- function(x) x
> A<- F(3)
>
> But that seems unnecessary...
>
> A<- 3
>
> Michael
>
> On Apr 25, 2012, at 10:06 PM, michaelyb<cel81009759 at gmail.com>  wrote:
>
>> Hello,
>>
>> I am trying to understand why the FUNCTION used in several codes, won't
>> create the object after it finishes running the code.
>> For instance, look at the following:
>>
>> Number<- function(x) {MyNumberIs<-x}
>>
>> When I run
>> Number(5)
>> Everything goes well, except that if I try to call the object MyNumberIs, I
>> won't find it.
>>
>> I understand that this function can assume many parameters, but why won't it
>> create the object?
>>
>> Besides, if I try "assing", it won't work either, no matter how I do it.
>>
>> Any advice/explanation?
>>
>> Thankk you very much!
>>
>> --
>> View this message in context: http://r.789695.n4.nabble.com/understanding-the-FUNCTION-function-tp4588681p4588681.html
>> Sent from the R help mailing list archive at Nabble.com.
>>
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>> and provide commented, minimal, self-contained, reproducible code.
> ______________________________________________
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