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Merging two columns of unequal length

4 messages · Bailey Hewitt, Mark Sharp, Jeff Newmiller +1 more

Bailey Hewitt
# 
Dear R Help,


I am trying to put together two columns of unequal length in a data frame. Unfortunately, so far I have been unsuccessful in the functions I have tried (such as cbind). The code I am currently using is : (I have highlighted the code that is not working)


y<- mydata[,2:75]

year <- mydata$Year

res <- data.frame()

for (i in 1:74){

  y.val <- y[,i]

  lake.lm= lm(y.val ~ year)

  lake.res=residuals(lake.lm)

  new.res <- data.frame(lake.res=lake.res)

  colnames(new.res) <- colnames(y)[i]

#cbind doesn't work because of the unequal lengths of my data columns

  res <- cbind(res, new.res)

  print(res)

}


mydata is a csv file with "Year" from 1950 on as my first column and then each proceeding column has a lake name and a day of year (single number) in each row.


Please let me know if there is any more information I can provide as I am new to emailing in this list. Thank you for your time!


Bailey Hewitt
Mark Sharp
# 
I did not look at the code, but note the following.

By definition,
1. You cannot highlight code in plan text, which is the format accepted by r-help.
2. You cannot have columns of different lengths in a dataframe.


R. Mark Sharp, Ph.D.
msharp at TxBiomed.org
CONFIDENTIALITY NOTICE: This e-mail and any files and/or...{{dropped:10}}
Jeff Newmiller
# 
You can't do that. You can either make a different data frame, or you can stack the data in additional rows. If you make your example reproducible, we may be able to give more specific help. 

Also,  post in plain text to avoid HTML code corruption. 

http://stackoverflow.com/questions/5963269/how-to-make-a-great-r-reproducible-example

http://adv-r.had.co.nz/Reproducibility.html
2 days later
Jim Lemon
# 
Hi Bailey,
I may be misunderstanding what you are doing as I can't work out how
you get unequal column lengths, but this may help:

myval<-matrix(sample(1:365,740,TRUE),ncol=74)
mydata<-as.data.frame(cbind(1950:1959,myval))
lakenames<-paste(rep(LETTERS[1:26],length.out=74),
 rev(rep(letters[1:25],length.out=74)),
 rep(letters[1:24],length.out=74),sep="")
names(mydata)<-c("Year",lakenames)
res<-vector("list",74)
for (i in 1:74){
 thisval<-mydata[,i+1]
 lake.lm<-lm(thisval ~ Year,mydata)
 res[[i]]<-residuals(lake.lm)
}
# this will cause an error with as.data.frame
res[[20]]<-res[[20]][-1]
# pad the short column with NA
res<-lapply(res,function(x,length.out) x[1:length.out],10)
res.df<-as.data.frame(res)
names(res.df)<-lakenames
print(res.df)

Jim
On Tue, Dec 13, 2016 at 10:41 AM, Bailey Hewitt <bailster at hotmail.com> wrote: