Why is any() only defined for a numeric and not logical data.frame?

Question

This appears to be quite surprising:

df1 <- data.frame(A=TRUE, B=FALSE)
df2 <- data.frame(A=1, B=2)

> any(df1)
Error in FUN(X[[i]], ...) :
  only defined on a data frame with all numeric variables

> any(df2)
[1] TRUE

This doesn't seem to be a bug because the error correctly states that any() will only work in the case where all variables within a data.frame are numeric.

But what is the reason for any() to work on all numeric variables and not when values are all logical?

Answer 1

any can work if it is vector as the documentation says

Given a set of logical vectors, is at least one of the values true?

In the OP's post, both examples are not vector s. The first is a data.frame with logical columns. If we go by way to satisfy the documentation ie create a logical vector, either convert to matrix (as a matrix is a vector anyway with some dim attributes)

any(as.matrix(df1))
#[1] TRUE

Or change it to a vector by unlist ing the list (a data.frame is a list of vector s aka columns of same length)

any(unlist(df1))

In the second case, there is a warning and it is doing some coercing

any(df2)
#[1] TRUE

Warning message: In any(c(1, 2), na.rm = FALSE) : coercing argument of type 'double' to logical