Extracting dataframe rows containing NAs in one column

Hi,

I am working on a data set which looks like this:
head(temp)
Day Month Year   PW  ROW
1   1     1 1959   NA 6.40
2   2     1 1959 6.65 6.35
3   3     1 1959 2.50 3.60
4   4     1 1959 0.60 2.25
5   5     1 1959 0.85 0.30
6   6     1 1959 0.00 2.20

I am trying to extract all the rows containing NA. I can extrat all the rows
without NAs in column 4 using
PWna<-temp[complete.cases(temp[,4]),]
head(PWna)
Day Month Year   PW  ROW
2   2     1 1959 6.65 6.35
3   3     1 1959 2.50 3.60
4   4     1 1959 0.60 2.25
5   5     1 1959 0.85 0.30
6   6     1 1959 0.00 2.20
7   7     1 1959 1.40 1.65

But can't figure out how to extract the rows WITH the NAs. Can anyone advise
me?

Thanks in advance

--
View this message in context: http://r.789695.n4.nabble.com/Extracting-dataframe-rows-containing-NAs-in-one-column-tp3937361p3937361.html
Sent from the R help mailing list archive at Nabble.com.
Hi,

I am working on a data set which looks like this:

head(temp)
  Day Month Year   PW  ROW
1   1     1 1959   NA 6.40
2   2     1 1959 6.65 6.35
3   3     1 1959 2.50 3.60
4   4     1 1959 0.60 2.25
5   5     1 1959 0.85 0.30
6   6     1 1959 0.00 2.20

I am trying to extract all the rows containing NA. I can extrat all the
rows without NAs in column 4 using 

PWna<-temp[complete.cases(temp[,4]),]
head(PWna)
  Day Month Year   PW  ROW
2   2     1 1959 6.65 6.35
3   3     1 1959 2.50 3.60
4   4     1 1959 0.60 2.25
5   5     1 1959 0.85 0.30
6   6     1 1959 0.00 2.20
7   7     1 1959 1.40 1.65

But can't figure out how to extract the rows WITH the NAs. Can anyone
advise me?

Thanks in advance

I am sure others will have cleaner approaches but how about ....

# Data
temp = data.frame(Day=1:6,Month=1, Year=c(NA,1959,NA,1959,1959,1959),
PW=c(6,7,8,NA,10,11))

# Extract Any Row Containing an NA
myNAs = temp[apply(temp,1,function(x) any(is.na(x))),]

HTH

Pete

--
View this message in context: http://r.789695.n4.nabble.com/Extracting-dataframe-rows-containing-NAs-in-one-column-tp3937361p3937523.html
Sent from the R help mailing list archive at Nabble.com.
I'm thinking you need to spend some time reading about subsetting in R:

temp[!complete.cases(temp),] # I don't think you need/want/should use the [,4]

Michael
Hi,

I am working on a data set which looks like this:

head(temp)
?Day Month Year ? PW ?ROW
1 ? 1 ? ? 1 1959 ? NA 6.40
2 ? 2 ? ? 1 1959 6.65 6.35
3 ? 3 ? ? 1 1959 2.50 3.60
4 ? 4 ? ? 1 1959 0.60 2.25
5 ? 5 ? ? 1 1959 0.85 0.30
6 ? 6 ? ? 1 1959 0.00 2.20

I am trying to extract all the rows containing NA. I can extrat all the rows
without NAs in column 4 using

PWna<-temp[complete.cases(temp[,4]),]
head(PWna)
?Day Month Year ? PW ?ROW
2 ? 2 ? ? 1 1959 6.65 6.35
3 ? 3 ? ? 1 1959 2.50 3.60
4 ? 4 ? ? 1 1959 0.60 2.25
5 ? 5 ? ? 1 1959 0.85 0.30
6 ? 6 ? ? 1 1959 0.00 2.20
7 ? 7 ? ? 1 1959 1.40 1.65

But can't figure out how to extract the rows WITH the NAs. Can anyone advise
me?

Thanks in advance

--
View this message in context: http://r.789695.n4.nabble.com/Extracting-dataframe-rows-containing-NAs-in-one-column-tp3937361p3937361.html
Sent from the R help mailing list archive at Nabble.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.