Filtering only a subset of a data frame

Asked Nov 05 '15 at 18:31

Active Nov 05 '15 at 18:35

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I know this question is an easy one however I could not find the answer anywhere.
How to filter only a part of a data frame that respect a condition x ?

For exemple if you have:

df=data.frame(c1=c("A","A","B","C","B","C","C"),c2=c(1,1,4,3,6,2,6))

I want to get rid of the rows of the df for which c1 equals "C" that do not respect the condition c2<=3 I cannot do it like this:

df[df$c1=="C",]<-dplyr::filter(df[df$c1=="C",],c2<=3)

Of course that does not work because the replacement does not have the same number of rows. What is the easy way to do this (Preferably using dplyr)?
One thing that could work is to include an if statement in the filter function. Is that possible ?

asked Nov 05 '15 at 18:31

jeandut

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read the documentation of `subset()` – jogo Nov 05 '15 at 18:33
`df %>% filter((c1=="C" & c2<=3)|c1!="C")` – Khashaa Nov 05 '15 at 18:36
Well that is a quick answer thank you Khashaa ! Did not think of that at all ! – jeandut Nov 05 '15 at 18:38
Is there a cleaner way to do it ? – jeandut Nov 05 '15 at 18:38
And @jeremycg apart from Khashaa's trick, which is more of a clever way around the problem than of a clean solution I do not see how this question could be a duplicate of the subject you mentioned. – jeandut Nov 05 '15 at 18:45

Filtering only a subset of a data frame

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