Re: [R] dataframe calculations based on certain values of a column

2014-03-27 Thread johannesradin...@gmail.com
Thanks, your solution using ave() works perfectly. /johannes -Ursprüngliche Nachricht- Von: Bert Gunter An: Johannes Radinger Cc: R help Gesendet: Mittwoch, 26. März 2014 16:45:43 GMT+00:00 Betreff: Re: [R] dataframe calculations based on certain values of a column I believe this

Re: [R] dataframe calculations based on certain values of a column

2014-03-26 Thread Noah Marconi
dplyr's group_by and mutate can create those columns for you: var1 <- c("a","b","c","a","b","c","a","b","c") var2 <- c("X","X","X","Y","Y","Y","Z","Z","Z") var3 <- c(1,2,2,5,2,6,7,4,4) df <- data.frame(var1,var2,var3) dt <- tbl_df(df) dt %.% group_by(var2) %.% mutate( div = var3[var1 =

Re: [R] dataframe calculations based on certain values of a column

2014-03-26 Thread Berend Hasselman
On 26-03-2014, at 17:09, Johannes Radinger wrote: > Hi, > > I have data in a dataframe in following structure > var1 <- c("a","b","c","a","b","c","a","b","c") > var2 <- c("X","X","X","Y","Y","Y","Z","Z","Z") > var3 <- c(1,2,2,5,2,6,7,4,4) > df <- data.frame(var1,var2,var3) > > Now I'd like to

Re: [R] dataframe calculations based on certain values of a column

2014-03-26 Thread Bert Gunter
I believe this will generalize. But check carefully! Using your example (Excellent!), use ave(): with(df,ave(seq_along(var1),var2,FUN=function(i) var3[i]/var3[i][var1[i]=="c"])) [1] 0.500 1.000 1.000 0.833 0.333 1.000 1.750 [8] 1.000 1.000 This is kind of a l

[R] dataframe calculations based on certain values of a column

2014-03-26 Thread Johannes Radinger
Hi, I have data in a dataframe in following structure var1 <- c("a","b","c","a","b","c","a","b","c") var2 <- c("X","X","X","Y","Y","Y","Z","Z","Z") var3 <- c(1,2,2,5,2,6,7,4,4) df <- data.frame(var1,var2,var3) Now I'd like to calculate relative values of var3. This values should be relative to th

Re: [R] Dataframe calculations

2010-03-22 Thread Petr PIKAL
t; not work, I do not yet grasp the coding, I am still a novice. > > Perhaps you or someone else could rerun your code on my original > > dataframe and see why it did not yield the correct results. > > > > Thank you, > > > > Mike > > > > -Original

Re: [R] Dataframe calculations

2010-03-19 Thread jim holtman
try this: # add 'date' to separate the data SCHEDULE2 <- within(SCHEDULE2, { date <- paste(YEAR, '-', MM, '-', DD, sep='') ARRIVE <- as.POSIXct(paste(date, ARRIVE)) DEPART <- as.POSIXct(paste(date, DEPART)) }) # process each day result <- lapply(split(SCHEDULE2, SCHEDULE2$date), functi

Re: [R] Dataframe calculations

2010-03-19 Thread Hosack, Michael
Thank you, Mike -Original Message- From: r-help-boun...@r-project.org [mailto:r-help-boun...@r-project.org] On Behalf Of Erich Neuwirth Sent: Friday, March 19, 2010 1:33 PM To: r-help@r-project.org Subject: Re: [R] Dataframe calculations Sorry, Oddly I got the use of odds and evens the wrong way

Re: [R] Dataframe calculations

2010-03-19 Thread Erich Neuwirth
g] On > Behalf Of Erich Neuwirth > Sent: Friday, March 19, 2010 11:38 AM > To: r-help@r-project.org > Subject: Re: [R] Dataframe calculations > > with the following code > > newvars()$ARRIVALS and newvars()$DEPARTURES > will give you the new variables you need. > >

Re: [R] Dataframe calculations

2010-03-19 Thread Hosack, Michael
t.org] On Behalf Of Erich Neuwirth Sent: Friday, March 19, 2010 11:38 AM To: r-help@r-project.org Subject: Re: [R] Dataframe calculations with the following code newvars()$ARRIVALS and newvars()$DEPARTURES will give you the new variables you need. -=-=-= addDelays <- function(arriveTime,wait

Re: [R] Dataframe calculations

2010-03-19 Thread Erich Neuwirth
with the following code newvars()$ARRIVALS and newvars()$DEPARTURES will give you the new variables you need. -=-=-= addDelays <- function(arriveTime,waitVec,travelVec){ start<-as.POSIXct(arriveTime,format="%H:%M:%S") delays<-as.vector(t(cbind(waitVec,travelVec))) newtimes<-format(start+

[R] Dataframe calculations

2010-03-19 Thread Hosack, Michael
Hi everyone, My question will probably seem simple to most of you, but I have spent many hours trying to solve it. I need to perform a series of sequential calculations on my dataframe that move across rows and down columns, and then repeat themselves at each unique 'MM' by 'DD' grouping. Specific