subset

I have the following data frame from which I would like to extract rows based on matching strings. > GEMA_EO5 gene_symbol fold_EO p_value RefSeq_ID BH_p_value KNG1 3.433049 8.56e-28 NM_000893,NM_001102416 1.234245e-24 REXO4 3.245317 1.78e-27 NM_020385 2.281367e-24 VPS29 3.827665 2.22e-25 NM_057180,NM_016226 2.560770e-22 CYP51A1 3.363149 5.95e-25 NM_000786,NM_001146152 6.239386e-22 TNPO2 4.707600 1.60e-23 NM_001136195,NM_001136196,NM_013433 1.538000e-20 NSDHL 2.703922 6.74e-23 NM_001129765,NM_015922 5.980454e-20 DPYSL2 5.097382 1.29e-22 NM_001386 1.062868e-19 So I would like to extract e.g. two

Background Before running a stepwise model selection, I need to remove missing values for any of my model terms. With quite a few terms in my model, there are therefore quite a few vectors that I need to look in for NA values (and drop any rows that have NA values in any of those vectors). However, there are also vectors that contain NA values that I do not want to use as terms / criteria for dropping rows. Question How do I drop rows from a dataframe which contain NA values for any of a list of vectors? I'm currently using the clunky method of a long series of !is.na's > my.df[!is.na(my.df

I would like to choose rows based on the subsets of their names, for example If I have the following data: data <- structure(c(91, 92, 108, 104, 87, 91, 91, 97, 81, 98), .Names = c("fee-", "fi", "fo-", "fum-", "foo-", "foo1234-", "123foo-", "fum-", "fum-", "fum-")) how do I select the rows matching 'foo'? using grep() doesn't work: grep('foo', data) returns: integer(0) what am I doing wrong? or, is there a better way? Thanks! You need to grep the names property of data, not the values property. For your example, use > grep("foo",names(data)) [1] 5 6 7 > data[grep("foo",names(data))] foo-

Possible Duplicate: Standard way to remove multiple elements from a dataframe I know in R that if you are searching for a subset of another group or matching based on id you'd use something like subset(df1, df1$id %in% idNums1) My question is how to do the opposite or choose items NOT matching a vector of ids. I tried using ! but get the error message subset(df1, df1$id !%in% idNums1) I think my backup is to do sometime like this: matches <- subset(df1, df1$id %in% idNums1) nonMatches <- df1[(-matches[,1]),] but I'm hoping there's something a bit more efficient. The expression df1$id %in%