"invalid argument type" error with all.equal. R

Question

all.equal() gives an "invalid argument type" error with these data. Any idea?

>matrix1
  1 2   3 4   5
1 0 0 0.0 0 0.0
2 1 0 0.0 0 0.0
3 0 1 0.0 0 0.0
4 0 0 0.5 0 0.5
5 0 0 1.0 0 0.0
>rowSums(matrix1)
1 2 3 4 5 
0 1 1 1 1 
> !all.equal(as.vector(rowSums(matrix1)), as.vector(rep(1, nrow(matrix1))), check.attributes=FALSE)
Error in !all.equal(as.vector(rowSums(matrix1)), as.vector(rep(1,  : 
  invalid argument type

Answer 1

all.equal is not returning that error, ! is:

> !""
Error in !"" : invalid argument type

This is because all.equal does not return a logical value when the two objects aren't roughly equal. This is documented in the first paragraph of ?all.equal, where it suggests you use isTRUE(all.equal(...)).