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How to remove NA’s from an R data frame that contains them at different places?
If NA values are placed at different positions in an R data frame then they cannot be easily removed in base R, we would be needing a package for that. The best package to solve this problem is dplyr and we can use summarise_each function of dplyr with na.omit to remove all the NA’s. But if we have more than one column in the data frame then the number of non-NA values must be same in all the columns.
Example
Consider the below data frame:
> x1<-rep(c(NA,2,3),times=c(7,10,3)) > x2<-rep(c(15,NA,24,NA,18),times=c(5,2,5,5,3)) > df1<-data.frame(x1,x2) > df1
Output
x1 x2 1 NA 15 2 NA 15 3 NA 15 4 NA 15 5 NA 15 6 NA NA 7 NA NA 8 2 24 9 2 24 10 2 24 11 2 24 12 2 24 13 2 NA 14 2 NA 15 2 NA 16 2 NA 17 2 NA 18 3 18 19 3 18 20 3 18
Loading dplyr package and removing NA’s from df1:
Example
> library(dplyr) > df1%>%summarise_each(funs(na.omit(.)))
Output
x1 x2 1 2 15 2 2 15 3 2 15 4 2 15 5 2 15 6 2 24 7 2 24 8 2 24 9 2 24 10 2 24 11 3 18 12 3 18 13 3 18
Let’s have a look at another example:
Example
> y1<-rep(c(545,NA,524,NA,589,NA,537,NA,541,NA),times=c(2,2,2,2,2,2,2,2,2,2)) > y2<-rep(c(NA,2.1,NA,1.7,NA),times=c(4,4,4,6,2)) > df2<-data.frame(y1,y2) > df2
Output
y1 y2 1 545 NA 2 545 NA 3 NA NA 4 NA NA 5 524 2.1 6 524 2.1 7 NA 2.1 8 NA 2.1 9 589 NA 10 589 NA 11 NA NA 12 NA NA 13 537 1.7 14 537 1.7 15 NA 1.7 16 NA 1.7 17 541 1.7 18 541 1.7 19 NA NA 20 NA NA
Removing NA’s from df2:
> df2%>%summarise_each(funs(na.omit(.)))
Output
y1 y2 1 545 2.1 2 545 2.1 3 524 2.1 4 524 2.1 5 589 1.7 6 589 1.7 7 537 1.7 8 537 1.7 9 541 1.7 10 541 1.7
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