Determines the location, i.e., index of the (first) minimum or maximum of a numeric (or logical) vector.

```
which.min(x)
which.max(x)
```

Missing and `NaN`

values are discarded.

an `integer`

or on 64-bit platforms, if
`length(x) =: n`

\(\ge 2^{31}\) an integer
valued `double`

of length 1 or 0 (iff `x`

has no
non-`NA`

s), giving the index of the *first* minimum or
maximum respectively of `x`

.

If this extremum is unique (or empty), the results are the same as
(but more efficient than) `which(x == min(x, na.rm = TRUE))`

or
`which(x == max(x, na.rm = TRUE))`

respectively.

For a `logical`

vector `x`

with both `FALSE`

and
`TRUE`

values, `which.min(x)`

and `which.max(x)`

return
the index of the first `FALSE`

or `TRUE`

, respectively, as
`FALSE < TRUE`

. However, `match(FALSE, x)`

or
`match(TRUE, x)`

are typically *preferred*, as they do
indicate mismatches.

Use `arrayInd()`

, if you need array/matrix indices instead
of 1D vector ones.

`which.is.max`

in package nnet differs in
breaking ties at random (and having a ‘fuzz’ in the definition
of ties).

# NOT RUN { x <- c(1:4, 0:5, 11) which.min(x) which.max(x) ## it *does* work with NA's present, by discarding them: presidents[1:30] range(presidents, na.rm = TRUE) which.min(presidents) # 28 which.max(presidents) # 2 ## Find the first occurrence, i.e. the first TRUE, if there is at least one: x <- rpois(10000, lambda = 10); x[sample.int(50, 20)] <- NA ## where is the first value >= 20 ? which.max(x >= 20) ## Also works for lists (which can be coerced to numeric vectors): which.min(list(A = 7, pi = pi)) ## -> c(pi = 2L) # }