R help - Aug 2008 - Function not returning a vector?

Why does:

(shape/scale) * (1:365/scale)^(shape - 1)

return a vector of numbers but calling a function

hasard(1:365,shape,scale)

defined like:

hazard <- function(x,shape,scale)
{
   return (shape/scale) * (x/scale)^(shape - 1)
}

Only return a single value? It is like x becomes a single value passed as an
argument.

Thank you.

Kevin

Try

hazard <- function(x,shape,scale)
{
   return ((shape/scale) * (x/scale)^(shape - 1))
}
hazard(1:365,1,1)

--jeff

rkevinburton at charter.net wrote:
> Why does:
>
> (shape/scale) * (1:365/scale)^(shape - 1)
>
> return a vector of numbers but calling a function
>
> hasard(1:365,shape,scale)
>
> defined like:
>
> hazard <- function(x,shape,scale)
> {
>    return (shape/scale) * (x/scale)^(shape - 1)
> }
>
> Only return a single value? It is like x becomes a single value passed as
an argument.
>
> Thank you.
>
> Kevin
>
> ______________________________________________
> R-help at r-project.org 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.
>

rkevinburton at charter.net wrote:
> Why does:
>
> (shape/scale) * (1:365/scale)^(shape - 1)
>
> return a vector of numbers but calling a function
>
> hasard(1:365,shape,scale)
>
> defined like:
>
> hazard <- function(x,shape,scale)
> {
>    return (shape/scale) * (x/scale)^(shape - 1)
> }
>
> Only return a single value? It is like x becomes a single value passed as
an argument.
>
>   
No, but "return" is syntactically like a function name. Watch your 
parentheses....

-- 
   O__  ---- Peter Dalgaard             ?ster Farimagsgade 5, Entr.B
  c/ /'_ --- Dept. of Biostatistics     PO Box 2099, 1014 Cph. K
 (*) \(*) -- University of Copenhagen   Denmark      Ph:  (+45) 35327918
~~~~~~~~~~ - (p.dalgaard at biostat.ku.dk)              FAX: (+45) 35327907

2008/8/28  <rkevinburton at charter.net>:
> hazard <- function(x,shape,scale)
> {
>   return (shape/scale) * (x/scale)^(shape - 1)
> }
>
> Only return a single value? It is like x becomes a single value passed as
an argument.
>
 It's evaluating return(shape/scale) and returning that! Add some
extra parentheses:

 return( (shape/scale) * (x/scale)^(shape-1) )

 seems to work. Are you a python programmer, perhaps?

Barry

<rkevinburton <at> charter.net> writes:
> 
> Why does:
> 
> (shape/scale) * (1:365/scale)^(shape - 1)
> 
> return a vector of numbers but calling a function
> 
> hasard(1:365,shape,scale)
> 
> defined like:
> 
> hazard <- function(x,shape,scale)
> {
>    return (shape/scale) * (x/scale)^(shape - 1)
> }
> 
> Only return a single value? It is like x becomes a single value passed as
an
argument.
> 
I believe you have a couple of typos. Your function is returning shape/scale 
only. Try:

hazard <- function(x,shape,scale)
{
     return ((shape/scale) * (x/scale)^(shape - 1))
}

On Thu, 28 Aug 2008, rkevinburton at charter.net wrote:
> Why does:
>
> (shape/scale) * (1:365/scale)^(shape - 1)
>
> return a vector of numbers but calling a function
>
> hasard(1:365,shape,scale)
>
> defined like:
>
> hazard <- function(x,shape,scale)
> {
>   return (shape/scale) * (x/scale)^(shape - 1)
     ^^^^^^^^^^^^^^^^^^^^

return() is a function, its argument is returned, everything afterwards is 
ignored. And shape/scalar is probably a scalar in your case...

So either change to

     return((shape/scale) * (x/scale)^(shape - 1))

or simply

            (shape/scale) * (x/scale)^(shape - 1)

without explicitely calling return().
> }
>
> Only return a single value? It is like x becomes a single value passed as
an argument.
>
> Thank you.
>
> Kevin
>
> ______________________________________________
> R-help at r-project.org 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.
>
>

> -----Original Message-----
> From: r-help-bounces at r-project.org 
> [mailto:r-help-bounces at r-project.org] On Behalf Of 
> rkevinburton at charter.net
> Sent: Thursday, August 28, 2008 11:36 AM
> To: r-help at r-project.org
> Subject: [R] Function not returning a vector?
> 
> Why does:
> 
> (shape/scale) * (1:365/scale)^(shape - 1)
> 
> return a vector of numbers but calling a function
> 
> hasard(1:365,shape,scale)
> 
> defined like:
> 
> hazard <- function(x,shape,scale)
> {
>    return (shape/scale) * (x/scale)^(shape - 1)
> }
> 
> Only return a single value? It is like x becomes a single 
> value passed as an argument.
> 
> Thank you.
> 
> Kevin
> 
Change your function definition to one of the following (I don't know which
is "better").

hazard <- function(x,shape,scale)
{  
   return( (shape/scale) * (x/scale)^(shape - 1) )
}

hazard <- function(x,shape,scale)
{
   (shape/scale) * (x/scale)^(shape - 1)
}

Hope this is helpful,

Dan

Daniel J. Nordlund
Washington State Department of Social and Health Services
Planning, Performance, and Accountability
Research and Data Analysis Division
Olympia, WA  98504-5204