R help - Aug 2011 - Help: find the index of the minimum of entries

Dear All,
I would like to ask a question on how to find the index of the minimum of
entries of a numeric vector, without using loops or user defined functions.
Suppose we have a vector:
a <- c(3,1,2)
then, 
min(a) = 1
and its index is 2.

Target:  how to get the index of this minimum? How to get the indices  if
multiple entries assume this same minimum?

Thank you,
Chee
	[[alternative HTML version deleted]]

Try which.min(a)

On Wed, Aug 24, 2011 at 1:03 PM, Chee Chen <chee.chen at yahoo.com>
wrote:
> Dear All,
> I would like to ask a question on how to find the index of the minimum of
entries of a numeric vector, without using loops or user defined functions.
> Suppose we have a vector:
> a <- c(3,1,2)
> then,
> min(a) = 1
> and its index is 2.
>
> Target: ?how to get the index of this minimum? How to get the indices ?if
multiple entries assume this same minimum?
>
> Thank you,
> Chee
> ? ? ? ?[[alternative HTML version deleted]]
>
> ______________________________________________
> 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.
>


-- 
Henrique Dallazuanna
Curitiba-Paran?-Brasil
25? 25' 40" S 49? 16' 22" O

which.min()

more generally

which(a==min(a))

Michael Weylandt

On Wed, Aug 24, 2011 at 12:03 PM, Chee Chen <chee.chen@yahoo.com> wrote:
> Dear All,
> I would like to ask a question on how to find the index of the minimum of
> entries of a numeric vector, without using loops or user defined functions.
> Suppose we have a vector:
> a <- c(3,1,2)
> then,
> min(a) = 1
> and its index is 2.
>
> Target:  how to get the index of this minimum? How to get the indices  if
> multiple entries assume this same minimum?
>
> Thank you,
> Chee
>        [[alternative HTML version deleted]]
>
> ______________________________________________
> R-help@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.
>
	[[alternative HTML version deleted]]