Changing column names of a data frame


Answers

I use this:

colnames(dataframe)[which(names(dataframe) == "columnName")] <- "newColumnName"
Question

I have a data frame called "newprice" (see below) and I want to change the column names in my program in R.

> newprice
   Chang.  Chang.   Chang.
1     100       36      136
2     120      -33       87
3     150       14      164

In fact this is what am doing:

names(newprice)[1]<-paste("premium")
names(newprice)[2]<-paste("change")
names(newprice)[3]<-paste("newprice") 

I have not put this in a loop because I want each column name to be different as you see.

When I paste my program into R console this is the output it gives me:

> names(newprice)[1]<-paste(“premium”)
Error: unexpected input in "names(newprice)[1]<-paste(“"
> names(newprice)[2]<-paste(“change”)
Error: unexpected input in "names(newprice)[2]<-paste(“"
> names(newprice)[3]<-paste(“newpremium”)
Error: unexpected input in "names(newprice)[3]<-paste(“"

I have equally tried using the c() function-for example c("premium"), instead of the paste() function, but to no avail.

Could someone help me to figure this out?




Did you try just:

names(newprice)[1]<-"premium"

?




My column names is as below

colnames(t)
[1] "Class"    "Sex"      "Age"      "Survived" "Freq" 

I want to change column name of Class and Sex

colnames(t)=c("STD","Gender","AGE","SURVIVED","FREQ")



If you need to rename not all but multiple column at once when you only know the old column names you can use colnames function and %in% operator. Example:

df = data.frame(bad=1:3, worse=rnorm(3), worst=LETTERS[1:3])

   bad      worse    worst
1   1 -0.77915455       A
2   2  0.06717385       B
3   3 -0.02827242       C

Now you want to change "bad" and "worst" to "good" and "best". You can use

colnames(df)[which(colnames(df) %in% c("bad","worst") )] <- c("good","best")

This results in

  good      worse  best
1    1 -0.6010363    A
2    2  0.7336155    B
3    3  0.9435469    C



You can just do the editing by:

newprice <- edit(newprice)

and change the column name manually.




I had the same issue and this piece of code worked out for me.

names(data)[names(data) == "oldVariableName"] <- "newVariableName"

In short, this code does the following:

names(data) looks into all the names in the dataframe (data)

[names(data) == oldVariableName] extracts the variable name (oldVariableName) you want to get renamed and <- "newVariableName" assigns the new variable name.




You could straightaway have done

names(newprice) <- c("premium","change","newprice")

The paste command that you are using takes 2 arguments atleast. It works like concatenate function in excel which is why it is giving you an error i think.