R help - Sep 2009 - Equivalent for Matematica function Which...

Dear All!

I'm looking for equivalent of Matematica function "Which" which
works as
follows:

z = Which[x<10,0.3, 10<=x<20,0.5, 20<=x<100,1]

where x is a vector

I can replace it with custom function with set of ifelse but I'm looking 
for simpler and faster (much faster) solution

best wishes
Jarek

Try this;

cut(x, breaks = c(0, 10, 20, 100), labels = c(0.3, .5, 1))

On Tue, Sep 29, 2009 at 3:11 PM, Jarek Jasiewicz <jarekj at amu.edu.pl>
wrote:
> Dear All!
>
> I'm looking for equivalent of Matematica function "Which"
which works as
> follows:
>
> z = Which[x<10,0.3, 10<=x<20,0.5, 20<=x<100,1]
>
> where x is a vector
>
> I can replace it with custom function with set of ifelse but I'm
looking for
> simpler and faster (much faster) solution
>
> best wishes
> Jarek
>
> ______________________________________________
> 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

Hi Jarek,
Take a look at ?which, ?ifelse and ?recode (car package).

HTH,
Jorge


On Tue, Sep 29, 2009 at 2:11 PM, Jarek Jasiewicz <> wrote:
> Dear All!
>
> I'm looking for equivalent of Matematica function "Which"
which works as
> follows:
>
> z = Which[x<10,0.3, 10<=x<20,0.5, 20<=x<100,1]
>
> where x is a vector
>
> I can replace it with custom function with set of ifelse but I'm
looking
> for simpler and faster (much faster) solution
>
> best wishes
> Jarek
>
> ______________________________________________
> 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]]

Hello, 
> I'm looking for equivalent of Matematica function "Which"
which works as
> follows:
> 
> z = Which[x<10,0.3, 10<=x<20,0.5, 20<=x<100,1]
> 
> where x is a vector
Unless someone happens to be a Mathematica user (very possible), I don't
know how we would answer the question.  You give an example of the function
call, but not what the function arguments or return value are.

There is an R function called "which", but what the Mathematica
"Which" is doing is entirely mysterious from your example.  What is in
"z" for instance??