Hi, I am trying to write a loop to recode my data from -999 to NA in R. What's the most efficient way to do this? Below is what I'm presently doing, which is inefficient. Thanks, Chris dat0 <- read.table("time1.dat") colnames(dat0) <- c("e1dq", "e1arcp", "e1dev", "s1prcp", "s1nrcp", "s1ints", "a1gpar", "a1pias", "a1devt") dat0[dat0$e1dq==-999.00000000,"e1dq"] <- NA dat0[dat0$e1arcp==-999.00000000,"e1arcp"] <- NA dat0[dat0$e1dev==-999.00000000,"e1dev"] <- NA dat0[dat0$s1prcp==-999.00000000,"s1prcp"] <- NA dat0[dat0$s1nrcp==-999.00000000,"s1nrcp"] <- NA dat0[dat0$s1ints==-999.00000000,"s1ints"] <- NA dat0[dat0$a1gpar==-999.00000000,"a1gpar"] <- NA dat0[dat0$a1pias==-999.00000000,"a1pias"] <- NA dat0[dat0$a1devt==-999.00000000,"a1devt"] <- NA [[alternative HTML version deleted]]
Try: dat0 <- read.table('tim1.dat', na = -999) On Wed, Mar 30, 2011 at 10:15 AM, Christopher Desjardins <cddesjardins at gmail.com> wrote:> Hi, > I am trying to write a loop to recode my data from -999 to NA in R. What's > the most efficient way to do this? Below is what I'm presently doing, which > is inefficient. Thanks, > Chris > > > ? dat0 <- read.table("time1.dat") > > colnames(dat0) <- c("e1dq", "e1arcp", "e1dev", "s1prcp", "s1nrcp", "s1ints", > "a1gpar", "a1pias", "a1devt") > > dat0[dat0$e1dq==-999.00000000,"e1dq"] <- NA > > dat0[dat0$e1arcp==-999.00000000,"e1arcp"] <- NA > > dat0[dat0$e1dev==-999.00000000,"e1dev"] <- NA > > dat0[dat0$s1prcp==-999.00000000,"s1prcp"] <- NA > > dat0[dat0$s1nrcp==-999.00000000,"s1nrcp"] <- NA > > dat0[dat0$s1ints==-999.00000000,"s1ints"] <- NA > > dat0[dat0$a1gpar==-999.00000000,"a1gpar"] <- NA > > dat0[dat0$a1pias==-999.00000000,"a1pias"] <- NA > > dat0[dat0$a1devt==-999.00000000,"a1devt"] <- NA > > ? ? ? ?[[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. >-- Henrique Dallazuanna Curitiba-Paran?-Brasil 25? 25' 40" S 49? 16' 22" O
On 30.03.2011 15:15, Christopher Desjardins wrote:> Hi, > I am trying to write a loop to recode my data from -999 to NA in R. What's > the most efficient way to do this? Below is what I'm presently doing, which > is inefficient. Thanks, > ChrisI think read.table(na.string="-999.00000000") is. Uwe Ligges> > dat0<- read.table("time1.dat") > > colnames(dat0)<- c("e1dq", "e1arcp", "e1dev", "s1prcp", "s1nrcp", "s1ints", > "a1gpar", "a1pias", "a1devt") > > dat0[dat0$e1dq==-999.00000000,"e1dq"]<- NA > > dat0[dat0$e1arcp==-999.00000000,"e1arcp"]<- NA > > dat0[dat0$e1dev==-999.00000000,"e1dev"]<- NA > > dat0[dat0$s1prcp==-999.00000000,"s1prcp"]<- NA > > dat0[dat0$s1nrcp==-999.00000000,"s1nrcp"]<- NA > > dat0[dat0$s1ints==-999.00000000,"s1ints"]<- NA > > dat0[dat0$a1gpar==-999.00000000,"a1gpar"]<- NA > > dat0[dat0$a1pias==-999.00000000,"a1pias"]<- NA > > dat0[dat0$a1devt==-999.00000000,"a1devt"]<- NA > > [[alternative HTML version deleted]] > > ______________________________________________ > R-help at r-project.org mailing list > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide http://www.R-project.org/posting-guide.html > and provide commented, minimal, self-contained, reproducible code.
Am 30.03.2011 09:15, schrieb Christopher Desjardins:> Hi, > I am trying to write a loop to recode my data from -999 to NA in R. What's > the most efficient way to do this? Below is what I'm presently doing, which > is inefficient. Thanks, > Chris > > > dat0<- read.table("time1.dat") > > colnames(dat0)<- c("e1dq", "e1arcp", "e1dev", "s1prcp", "s1nrcp", "s1ints", > "a1gpar", "a1pias", "a1devt") > > dat0[dat0$e1dq==-999.00000000,"e1dq"]<- NA > > dat0[dat0$e1arcp==-999.00000000,"e1arcp"]<- NA > > dat0[dat0$e1dev==-999.00000000,"e1dev"]<- NA > > dat0[dat0$s1prcp==-999.00000000,"s1prcp"]<- NA > > dat0[dat0$s1nrcp==-999.00000000,"s1nrcp"]<- NA > > dat0[dat0$s1ints==-999.00000000,"s1ints"]<- NA > > dat0[dat0$a1gpar==-999.00000000,"a1gpar"]<- NA > > dat0[dat0$a1pias==-999.00000000,"a1pias"]<- NA > > dat0[dat0$a1devt==-999.00000000,"a1devt"]<- NA >Given that all your variables share the same code for missing values, e.g. -99, you could do the following: df <- data.frame(a = c(1, 2, -99), b = c(33, -99, 22), c = c(-99, -99, 101)) df df[df == -99] <- NA df HTH, Bernd
On Wed, 2011-03-30 at 08:15 -0500, Christopher Desjardins wrote:> Hi, > I am trying to write a loop to recode my data from -999 to NA in R. What's > the most efficient way to do this? Below is what I'm presently doing, which > is inefficient. Thanks, > Chris > > > dat0 <- read.table("time1.dat")dat0 <- read.table("time1.dat", na.strings = c("NA","-999")) would seem the easiest option. Do read ?read.table for details. HTH G> colnames(dat0) <- c("e1dq", "e1arcp", "e1dev", "s1prcp", "s1nrcp", "s1ints", > "a1gpar", "a1pias", "a1devt") > > dat0[dat0$e1dq==-999.00000000,"e1dq"] <- NA > > dat0[dat0$e1arcp==-999.00000000,"e1arcp"] <- NA > > dat0[dat0$e1dev==-999.00000000,"e1dev"] <- NA > > dat0[dat0$s1prcp==-999.00000000,"s1prcp"] <- NA > > dat0[dat0$s1nrcp==-999.00000000,"s1nrcp"] <- NA > > dat0[dat0$s1ints==-999.00000000,"s1ints"] <- NA > > dat0[dat0$a1gpar==-999.00000000,"a1gpar"] <- NA > > dat0[dat0$a1pias==-999.00000000,"a1pias"] <- NA > > dat0[dat0$a1devt==-999.00000000,"a1devt"] <- NA > > [[alternative HTML version deleted]] > > ______________________________________________ > R-help at r-project.org mailing list > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide http://www.R-project.org/posting-guide.html > and provide commented, minimal, self-contained, reproducible code.-- %~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~% Dr. Gavin Simpson [t] +44 (0)20 7679 0522 ECRC, UCL Geography, [f] +44 (0)20 7679 0565 Pearson Building, [e] gavin.simpsonATNOSPAMucl.ac.uk Gower Street, London [w] http://www.ucl.ac.uk/~ucfagls/ UK. WC1E 6BT. [w] http://www.freshwaters.org.uk %~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%
It could be done in a large number of ways depending on how often you need it etc. You might take a look at defmacro in package gtools: # library(gtools) setNA <- macro(df, var, values) { df$var[df$var %in% values] <- NA } then instead of> dat0[dat0$e1dq==-999.00000000,"e1dq"] <- NAyou could have setNA(dat0, e1dq, -999) Otherwise, with lapply, you could have dat0.na_ized <- lapply(dat0, function(x) x[x%in% 999.00000] <- NA) (but I didn't try this so I can't tell if you need to use as.data.frame on the result or not) Kenn On Wed, Mar 30, 2011 at 4:15 PM, Christopher Desjardins <cddesjardins at gmail.com> wrote:> Hi, > I am trying to write a loop to recode my data from -999 to NA in R. What's > the most efficient way to do this? Below is what I'm presently doing, which > is inefficient. Thanks, > Chris > > > ? dat0 <- read.table("time1.dat") > > colnames(dat0) <- c("e1dq", "e1arcp", "e1dev", "s1prcp", "s1nrcp", "s1ints", > "a1gpar", "a1pias", "a1devt") > > dat0[dat0$e1dq==-999.00000000,"e1dq"] <- NA > > dat0[dat0$e1arcp==-999.00000000,"e1arcp"] <- NA > > dat0[dat0$e1dev==-999.00000000,"e1dev"] <- NA > > dat0[dat0$s1prcp==-999.00000000,"s1prcp"] <- NA > > dat0[dat0$s1nrcp==-999.00000000,"s1nrcp"] <- NA > > dat0[dat0$s1ints==-999.00000000,"s1ints"] <- NA > > dat0[dat0$a1gpar==-999.00000000,"a1gpar"] <- NA > > dat0[dat0$a1pias==-999.00000000,"a1pias"] <- NA > > dat0[dat0$a1devt==-999.00000000,"a1devt"] <- NA > > ? ? ? ?[[alternative HTML version deleted]] > > ______________________________________________ > R-help at r-project.org mailing list > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide http://www.R-project.org/posting-guide.html > and provide commented, minimal, self-contained, reproducible code. >
Try using a loop like the following dat0 <- read.table("time1.dat") id <- c("e1dq", "e1arcp", "e1dev", "s1prcp", "s1nrcp","s1ints","a1gpar", "a1pias", "a1devt") for (a in 1:length(id)) { dat0[dat0$id[a]==-999.00000000,as.character(id[a])] <- NA } -- Muhammad Rahiz Researcher & DPhil Candidate (Climate Systems & Policy) School of Geography & the Environment University of Oxford On Wed, 30 Mar 2011, Christopher Desjardins wrote:> Hi, > I am trying to write a loop to recode my data from -999 to NA in R. What's > the most efficient way to do this? Below is what I'm presently doing, which > is inefficient. Thanks, > Chris > > > dat0 <- read.table("time1.dat") > > colnames(dat0) <- c("e1dq", "e1arcp", "e1dev", "s1prcp", "s1nrcp", "s1ints", > "a1gpar", "a1pias", "a1devt") > > dat0[dat0$e1dq==-999.00000000,"e1dq"] <- NA > > dat0[dat0$e1arcp==-999.00000000,"e1arcp"] <- NA > > dat0[dat0$e1dev==-999.00000000,"e1dev"] <- NA > > dat0[dat0$s1prcp==-999.00000000,"s1prcp"] <- NA > > dat0[dat0$s1nrcp==-999.00000000,"s1nrcp"] <- NA > > dat0[dat0$s1ints==-999.00000000,"s1ints"] <- NA > > dat0[dat0$a1gpar==-999.00000000,"a1gpar"] <- NA > > dat0[dat0$a1pias==-999.00000000,"a1pias"] <- NA > > dat0[dat0$a1devt==-999.00000000,"a1devt"] <- NA > > [[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. >