R: Selecting rows from a dataframe based on a set of values of interest appearing in certain columns

Question

I have a large dataframe of doctor visit records. I want to select only those rows in which at least one of the 11 diagnosis codes listed is found in a specified set of diagnosis codes that I am interested in. The dataframe is 18 columns by 39,019 rows. I am interested in diagnosis codes in columns 6:16. Here is a data sample for these 11 diagnosis columns only (to protect identifiable info): ``` diag1 diag2 diag3 diag4 diag5 diag6 diag7 diag8 diag9 diag10 diag11 786 272 401 782 250 91912 530 NA NA NA NA 845 530 338 311 NA NA NA NA NA NA NA ``` Here is the code I have tried to use: ``` mydiag <- c(401, 410, 411, 413, 415:417, 420:429, 434, 435, 444, 445, 451, 460:466, 480:486, 490:493, 496, 786) y = apply(dt[,paste("diag", 1:11, sep="")], 1, function(x) sum((any(x !=NA %in% mydiag)))) y = as.data.frame(y) ``` As you can see, in the 2 example rows I provided, I would want to keep the first row but throw out the second row because it doesn't have any of the codes I want. The code sample…

Accepted Answer

I think you're overcomplicating things with the `!=NA` bit in there. Since NA doesn't appear in `mydiag`, you can drop it completely. So your apply statement then can become:

```
goodRows <- apply(dat, 1, function(x) any(x %in% mydiag))
dat[goodRows,]
#---------------
  diag1 diag2 diag3 diag4 diag5 diag6 diag7 diag8 diag9 diag10 diag11
1   786   272   401   782   250 91912   530    NA    NA     NA     NA
```

R: Selecting rows from a dataframe based on a set of values of interest appearing in certain columns

Solution

Problem