Print rows if condition met, R

Question

I'm trying to figure out how to print the rows in my logical data.frame that have a TRUE 's in them, example:

DATA:

structure(list(X1 = c(TRUE, TRUE, FALSE, TRUE, FALSE, FALSE, 
TRUE, FALSE, FALSE, FALSE, FALSE, FALSE, TRUE, FALSE, FALSE, 
TRUE, FALSE, FALSE, FALSE, FALSE, TRUE, TRUE, FALSE, FALSE, TRUE, 
TRUE, FALSE, FALSE, FALSE, TRUE, TRUE, TRUE, TRUE, FALSE, FALSE, 
TRUE, TRUE, TRUE, FALSE, TRUE, TRUE, FALSE, TRUE, FALSE, TRUE, 
TRUE, TRUE, TRUE, TRUE, TRUE, TRUE, FALSE, TRUE, FALSE, TRUE, 
TRUE, TRUE, TRUE, TRUE, TRUE, FALSE, FALSE, FALSE, TRUE, FALSE, 
FALSE, TRUE, FALSE, TRUE, TRUE, FALSE, TRUE, FALSE, FALSE, FALSE, 
TRUE, FALSE, TRUE, FALSE, FALSE, FALSE, TRUE, TRUE, TRUE, FALSE, 
FALSE, FALSE, FALSE, TRUE, TRUE, TRUE, TRUE, TRUE, FALSE, FALSE, 
TRUE, FALSE, TRUE, TRUE, FALSE), X2 = c(TRUE, TRUE, FALSE, FALSE, 
TRUE, TRUE, FALSE, FALSE, FALSE, FALSE, FALSE, FALSE, FALSE, 
TRUE, TRUE, FALSE, FALSE, TRUE, FALSE, TRUE, TRUE, FALSE, TRUE, 
TRUE, FALSE, TRUE, FALSE, TRUE, FALSE, FALSE, TRUE, FALSE, FALSE, 
FALSE, TRUE, TRUE, TRUE, TRUE, FALSE, FALSE, TRUE, TRUE, TRUE, 
FALSE, TRUE, TRUE, FALSE, TRUE, TRUE, FALSE, TRUE, FALSE, FALSE, 
FALSE, TRUE, TRUE, FALSE, FALSE, FALSE, TRUE, FALSE, TRUE, FALSE, 
TRUE, TRUE, FALSE, TRUE, FALSE, FALSE, TRUE, FALSE, TRUE, FALSE, 
FALSE, FALSE, TRUE, TRUE, FALSE, TRUE, FALSE, TRUE, FALSE, FALSE, 
FALSE, TRUE, TRUE, TRUE, TRUE, TRUE, TRUE, FALSE, TRUE, TRUE, 
TRUE, TRUE, TRUE, FALSE, TRUE, TRUE, TRUE), X3 = c(TRUE, FALSE, 
TRUE, FALSE, FALSE, TRUE, FALSE, TRUE, TRUE, FALSE, TRUE, FALSE, 
FALSE, TRUE, TRUE, TRUE, FALSE, FALSE, TRUE, FALSE, FALSE, TRUE, 
FALSE, FALSE, TRUE, FALSE, FALSE, TRUE, TRUE, FALSE, FALSE, FALSE, 
TRUE, TRUE, TRUE, TRUE, FALSE, TRUE, TRUE, TRUE, TRUE, FALSE, 
FALSE, TRUE, FALSE, TRUE, TRUE, TRUE, TRUE, FALSE, FALSE, TRUE, 
TRUE, TRUE, TRUE, FALSE, FALSE, FALSE, FALSE, TRUE, TRUE, FALSE, 
FALSE, TRUE, TRUE, TRUE, FALSE, FALSE, TRUE, TRUE, TRUE, FALSE, 
TRUE, FALSE, TRUE, FALSE, FALSE, FALSE, FALSE, TRUE, FALSE, FALSE, 
FALSE, TRUE, TRUE, TRUE, FALSE, TRUE, FALSE, TRUE, TRUE, TRUE, 
FALSE, TRUE, TRUE, TRUE, TRUE, TRUE, FALSE, FALSE)), .Names = c("X1", 
"X2", "X3"), row.names = c(NA, -100L), class = "data.frame")

FUNCTION (not working):

t(apply(X = data, MARGIN = 1, FUN =  function(x){x[x == TRUE,]}))

I want the TRUE check to be applied across each row ( MARGIN = 1 )and then return that row if there is even one TRUE statement.

Answer 1

You shouldn't use apply for subsetting directly. You can use apply to make an logical vector you can then use for indexing. (And really you should avoid apply with data.frames unless all the columns are of the same type.) If you really only have TRUE/FALSE values you can do a quick trick with rowSums. If you've saved your data in a data.frame called dd , you can do

dd[ rowSums(dd)>0 , ]

to get all the rows with at least one TRUE. If you wanted to use apply to find the desired rows, you could use the any() function which checks for at least one TRUE value.

dd[ apply(dd, 1, any), ]