damn, that's pretty clever. +1

thanks

On Thu, Feb 9, 2012 at 8:11 PM, ilai <keren@math.montana.edu> wrote:

> Your attempt was just overly complicated. All you needed was
>
> threshold <- c( .2 , .4 , .5 )[ df$track ]
> df$value <- pmax(threshold, df$value)
> df # desired outcome
>
> Cheers
>
> On Thu, Feb 9, 2012 at 3:56 PM, Idris Raja <idris.raja@gmail.com> wrote:
> > # I have a dataframe in the following form:
> >
> > track <- c(rep('A', 3), rep('B', 4), rep('C', 4))
> > value <- c(0.15, 0.25, 0.35, 0.05, 0.99, 0.32, 0.13, 0.80, 0.75, 0.60,
> 0.44)
> > df <- data.frame(track=factor(track), value=value)
> >
> > #> print(df)
> >   #track value
> > #1      A  0.15
> > #2      A  0.25
> > #3      A  0.35
> > #4      B  0.05
> > #5      B  0.99
> > #6      B  0.32
> > #7      B  0.13
> > #8      C  0.80
> > #9      C  0.75
> > #10     C  0.60
> > #11     C  0.44
> >
> >
> > # If any of the values are below a threshold value, I want to replace it
> > with the
> > # threshold value. The twist is that there is a different threshold value
> > for
> > # every track.
> >
> > # I tried something like this, but it's not working
> >
> > threshold <- list()
> > threshold['A'] <- 0.2
> > threshold['B'] <- 0.4
> > threshold['C'] <- 0.5
> >
> >
> > for (track in levels(df$track)){
> >    df[df$track==track,]$outcome <- pmax(df[df$track==track,]$outcome,
> >                                         threshold[track])
> > }
> > # Warning messages:
> > # 1: In is.na(mmm) : is.na() applied to non-(list or vector) of type
> 'NULL'
> > # 2: In is.na(mmm) : is.na() applied to non-(list or vector) of type
> 'NULL'
> > # 3: In is.na(mmm) : is.na() applied to non-(list or vector) of type
> 'NULL'
> >
> >
> > #******************
> > # Desired Results:
> >
> > #> print(df)
> >   #track value
> > #1      A  0.20 # value changed
> > #2      A  0.25
> > #3      A  0.35
> > #4      B  0.40 # value changed
> > #5      B  0.99
> > #6      B  0.40 # value changed
> > #7      B  0.40 # value changed
> > #8      C  0.80
> > #9      C  0.75
> > #10     C  0.60
> > #11     C  0.50 # value changed
> >
> >
> > # Any ideas? Thanks for reading.
> >
> >        [[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]]

