In R code, it is legal to use
F to mean
FALSE respectively. However,
FALSE are reserved words – they can only be used to mean
FALSE. Code like
will return a syntax error.
T and F are not so protected. This means that code like
is completely legal.
Of course, you wouldn’t deliberately do this (except perhaps at the start of April), but it is possible to do it accidentally. Perhaps, for example, a column of a
data.frame is named
F and you have attached it. It is best to be safe and always use
FALSE. This also makes code easier to read.