Re: [R] Speeding things up

From: Zoltan Kmetty <zkmetty_at_gmail.com>
Date: Mon 08 Jan 2007 - 11:32:41 GMT

Hi Benjamin!

##TRY THIS: THIS MAYBE MUCH FASTER, BECAUSE ONLY WORK WITH THE IMPORTANAT ROWS - HOPE NO ERROR IN IT:D puffer1 <- as.matrix(sdata$value)
puffer2 <- rbind(as.matrix(puffer1[2:nrow(puffer1),1]),0)

speedy <- puffer1 > puffer2
speedy <- (as.matrix(which(puffer1==TRUE)))+1 sdata$ddtd[]=0

for(cnt in 1:nrow(speedy))

       {

sdata$ddtd[speedy[cnt,1]] <- sdata$ddtd[(speedy[cnt,1]) - 1] + sdata$value[(speedy[cnt,1]) - 1] -sdata$value[speedy[cnt,1]]

       }
       return(sdata)



#Zoltan

2007/1/8, Benjamin Dickgiesser <dickgiesser@gmail.com>:
>
> Hi,
>
> is it possible to do this operation faster? I am going over 35k data
> entries and this takes quite some time.
>
> for(cnt in 2:length(sdata$date))
> {
>
> if(sdata$value[cnt] < sdata$value[cnt - 1]) {
> sdata$ddtd[cnt] <- sdata$ddtd[cnt - 1] +
> sdata$value[cnt - 1] -
> sdata$value[cnt]
> }
> else sdata$ddtd[cnt] <- 0
>
> }
> return(sdata)
>
> Thank you,
> Benjamin
>
> ______________________________________________
> R-help@stat.math.ethz.ch 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@stat.math.ethz.ch 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. Received on Mon Jan 08 22:54:02 2007

Archive maintained by Robert King, hosted by the discipline of statistics at the University of Newcastle, Australia.
Archive generated by hypermail 2.1.8, at Mon 08 Jan 2007 - 12:30:29 GMT.

Mailing list information is available at https://stat.ethz.ch/mailman/listinfo/r-help. Please read the posting guide before posting to the list.