R help - Jun 2013 - find closest value in a vector based on another vector values

Dear All,

would you please provide your thoughts on the following:
let us say I have:

a <-c(1,5,8,15,32,69)
b <-c(8.5,33)

and I would like to extract from "a" the two values that are closest
to the values in "b", where the length of this vectors may change but
b will allways be shorter than "a". So at the end based on this
example I should have the result "f" as

f <-c(8,32)

appreciate the help,

Andras

Dear Andras,

Try
> a[findInterval(b, a)]
[1]  8 32

HTH,
Jorge.-


On Tue, Jun 18, 2013 at 10:34 PM, Andras Farkas <motyocska@yahoo.com>
wrote:
> Dear All,
>
> would you please provide your thoughts on the following:
> let us say I have:
>
> a <-c(1,5,8,15,32,69)
> b <-c(8.5,33)
>
> and I would like to extract from "a" the two values that are
closest to
> the values in "b", where the length of this vectors may change
but b will
> allways be shorter than "a". So at the end based on this example
I should
> have the result "f" as
>
> f <-c(8,32)
>
> appreciate the help,
>
> Andras
>
> ______________________________________________
> 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]]

Hi,
Perhaps this works:

a[sapply(b,function(x) which.min(abs(x-a)))]
#[1]? 8 32

A.K.

----- Original Message -----
From: Andras Farkas <motyocska at yahoo.com>
To: r-help at r-project.org
Cc: 
Sent: Tuesday, June 18, 2013 8:34 AM
Subject: [R] find closest value in a vector based on another vector values

Dear All,

would you please provide your thoughts on the following:
let us say I have:

a <-c(1,5,8,15,32,69)
b <-c(8.5,33)

and I would like to extract from "a" the two values that are closest
to the values in "b", where the length of this vectors may change but
b will allways be shorter than "a". So at the end based on this
example I should have the result "f" as

f <-c(8,32)

appreciate the help,

Andras

______________________________________________
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.