isTRUE(x)
TRUE
if
x
is a
logical vector of length one whose value is
TRUE
.
Otherwise
FALSE
.
Attributes of
x
, such as names or dimensions,
are ignored.
isTRUE is handy for testing the results of functions like all.equal() and getOption(), which may return TRUE on success and character strings or NULL on failure.
This function differs slightly from the R implementation of
isTRUE
,
which is
identical(TRUE, x)
, and thus
would return
FALSE
for
isTRUE(c(one=1)==1)
.
isTRUE(all.equal(sqrt(14), sqrt(2)*sqrt(7))) && isTRUE(all.equal(1:2,1:3)) # FALSE
isTRUE(getOption("unusualOption")) # FALSE if this option not set or FALSE options(unusualOption = TRUE) isTRUE(getOption("unusualOption")) # TRUE
isTRUE(c(Value=TRUE)) # TRUE in S-PLUS, FALSE in R