Dimitri Liakhovitski
2011-Mar-11 18:26 UTC
[R] nesting same set of values with each level of another set of values
Hello!
The code below works and does what I need it to do.
However, I think the way I create myframe (last step) is very
un-R-like and probably not very efficient. I am sure there are better,
more R-appropriate methods.
Any pointers?
Thanks a lot!
Dimitri
# Step 1: Creating a vector of dates:
mydates<-seq(as.Date("2008-12-29"), length = 50, by =
"week")
(mydates)
# Step 2: Creating a vector of units:
units<-1:20
(units)
### Step3: Creating a data frame with 2 columns: all units stacked
(col 1) with all dates in each (col 2):
myframe<-NULL
for(i in 1:length(units)){ # i<-1
myframe[[i]]<-data.frame(unit=rep(units[i],length(mydates)),Weeks=mydates)
}
myframe<-do.call(rbind,myframe)
str(myframe)
head(myframe,110)
--
Dimitri Liakhovitski
Ninah Consulting
www.ninah.com
David Winsemius
2011-Mar-11 18:46 UTC
[R] nesting same set of values with each level of another set of values
On Mar 11, 2011, at 1:26 PM, Dimitri Liakhovitski wrote:> Hello! > > The code below works and does what I need it to do. > However, I think the way I create myframe (last step) is very > un-R-like and probably not very efficient. I am sure there are better, > more R-appropriate methods. > Any pointers? > Thanks a lot! > Dimitri > > # Step 1: Creating a vector of dates: > mydates<-seq(as.Date("2008-12-29"), length = 50, by = "week") > (mydates) > > # Step 2: Creating a vector of units: > units<-1:20 > (units) >You might want to see if this is more "R-like: myframe <- expand.grid(unit=units, Weeks=mydates) (It will probably be a lot faster if you need to "scale up" this operation.) -- David.> ### Step3: Creating a data frame with 2 columns: all units stacked > (col 1) with all dates in each (col 2): > myframe<-NULL > for(i in 1:length(units)){ # i<-1 > myframe[[i]]<- > data.frame(unit=rep(units[i],length(mydates)),Weeks=mydates) > } > myframe<-do.call(rbind,myframe) > str(myframe) > head(myframe,110) > > > -- > Dimitri Liakhovitski > Ninah Consulting > www.ninah.com > > ______________________________________________ > 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.David Winsemius, MD West Hartford, CT
Dimitri Liakhovitski
2011-Mar-11 19:03 UTC
[R] nesting same set of values with each level of another set of values
Thanks a lot, David! Exactly what I was looking for! Dimitri On Fri, Mar 11, 2011 at 1:46 PM, David Winsemius <dwinsemius at comcast.net> wrote:> > On Mar 11, 2011, at 1:26 PM, Dimitri Liakhovitski wrote: > >> Hello! >> >> The code below works and does what I need it to do. >> However, I think the way I create myframe (last step) is very >> un-R-like and probably not very efficient. I am sure there are better, >> more R-appropriate methods. >> Any pointers? >> Thanks a lot! >> Dimitri >> >> # Step 1: Creating a vector of dates: >> mydates<-seq(as.Date("2008-12-29"), length = 50, by = "week") >> (mydates) >> >> # Step 2: Creating a vector of units: >> units<-1:20 >> (units) >> > > You might want to see if this is more "R-like: > > myframe <- expand.grid(unit=units, Weeks=mydates) > > (It will probably be a lot faster if you need to "scale up" this operation.) > > -- > David. >> >> ### Step3: Creating a data frame with 2 columns: all units stacked >> (col 1) with all dates in each (col 2): >> myframe<-NULL >> for(i in 1:length(units)){ ?# i<-1 >> >> ?myframe[[i]]<-data.frame(unit=rep(units[i],length(mydates)),Weeks=mydates) >> } >> myframe<-do.call(rbind,myframe) >> str(myframe) >> head(myframe,110) >> >> >> -- >> Dimitri Liakhovitski >> Ninah Consulting >> www.ninah.com >> >> ______________________________________________ >> 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. > > David Winsemius, MD > West Hartford, CT > >-- Dimitri Liakhovitski Ninah Consulting www.ninah.com