Message-ID: <092fe0057f9177ddb883b6092636ef11@huesing.name>
Date: 2009-02-26T13:52:51Z
From: Johannes Hüsing
Subject: Re : Have a function like the "_n_" in R ? (Automatic count function )
In-Reply-To: <402088.1702.qm@web23207.mail.ird.yahoo.com>
If you are in the context of a data frame (which is closest to the
concept
of a "data set" in SAS), the 1:nrow(df) is closest to what you may look
for.
For instance:
data(iris)
.n. <- 1:nrow(iris)
You may notice that this number is not very idiomatic in R.
If you have something like:
if(_N_ > 50) then output;
in R you can simply put
iris[-(1:50),]
without using an explicit counter variable.
In the context of a matrix, the row() and col() functions may do what
you want.
Am 25.02.2009 um 15:34 schrieb justin bem:
> R is more flexible that SAS. You?have many functions for loop e.g.
> for, while, repeat. You also have dim and length?functions to get
> objects dimensions.
>
> i<-0
> dat<-matrix(c(1, runif(1), .Random.seed[1]),nr=1)
> repeat{
> ??? i=i+1
> ??? dat<-rbind(dat, matrix(c(1+i, runif(1), .Random.seed[1]),nr=1))
> ??? if (i==4) break
> }
>
> colnames(dat)<-c("counter", "x","seed")
> dat
>
> ?Justin BEM
> BP 1917 Yaound?
> T?l (237) 99597295
> (237) 22040246
>
>
>
>
> ________________________________
> De : Nash <morrison at ibms.sinica.edu.tw>
> ? : r-help <r-help at r-project.org>
> Envoy? le : Mercredi, 25 F?vrier 2009, 13h25mn 18s
> Objet?: [R] Have a function like the "_n_" in R ? (Automatic count
> function )
>
>
> Have the counter function in R ?
>
> if we use the software SAS
>
> /*** SAS Code **************************/
> data tmp(drop= i);
> retain seed x 0;
> do i = 1 to 5;
> ??? call ranuni(seed,x);
> ??? output;
> end;
> run;
>
> data new;
> counter=_n_;? ***** this keyword _n_ ****;
> set tmp;
> run;
>
> /*
> _n_ (Automatic variables)
> are created automatically by the DATA step or by DATA step statements.
> */
>
> /*** Output ********************************
> counter??? ? ? seed? ? ? ? ? ? x
> 1??? 584043288??? ? ? ? ? 0.27197
> 2??? 935902963??? ? ? ? ? 0.43581
> 3??? 301879523??? ? ? ? ? 0.14057
> 4??? 753212598??? ? ? ? ? 0.35074
> 5??? 1607264573??? 0.74844
>
> ********************************************/
>
> Have a function like the "_n_" in R ?
>
>
> --
> Nash - morrison at ibms.sinica.edu.tw
>
> ______________________________________________
> 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.
>
>
>
>
> [[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.