Index of the Maximum

Returns the index of the maximum value along an axis. Ties are broken by returning the smallest index.

Usage

nv_argmax(x, axis = NULL, drop = TRUE, nan_rm = FALSE)

Arguments

x

(arrayish)
Input array.

axis

(integer(1) | NULL)
Axis along which to find the index. Negative values count from the end, i.e. -1 refers to the last axis. If NULL (default), uses the last axis.

drop

(logical(1))
If TRUE (default) the reduced axis is removed; if FALSE it is kept with size 1.

nan_rm

(logical(1))
How to handle NaN values in floating-point inputs. If FALSE (default), NaN propagates. If TRUE, NaN values are skipped.

Value

arrayish of dtype i32
Same shape as x with axis removed (or set to 1 if drop = FALSE).

NaN handling

With nan_rm = FALSE (default), if any entry along the reduced axis is NaN, the returned index points at the first such NaN. With nan_rm = TRUE, NaN entries are skipped.

See also

nv_argmin(), nv_reduce_max().

Examples

nv_argmax(nv_array(c(3, 1, 4, 1, 5, 9, 2, 6)))
#> AnvlArray
#>  6
#> [ CPUi32{} ] 
nv_argmax(nv_matrix(c(3, 1, 5, 2, 4, 0), nrow = 2, byrow = TRUE),
  axis = 2L
)
#> AnvlArray
#>  3
#>  2
#> [ CPUi32{2} ] 
nv_argmax(nv_array(c(1, NaN, 3)))
#> AnvlArray
#>  2
#> [ CPUi32{} ] 
nv_argmax(nv_array(c(1, NaN, 3)), nan_rm = TRUE)
#> AnvlArray
#>  3
#> [ CPUi32{} ]