aperm {base} | R Documentation |
Transpose an array by permuting its dimensions and optionally resizing it.
aperm(a, perm, ...)
## Default S3 method:
aperm(a, perm = NULL, resize = TRUE, ...)
## S3 method for class 'table'
aperm(a, perm = NULL, resize = TRUE, keep.class = TRUE, ...)
a |
the array to be transposed. |
perm |
the subscript permutation vector, usually a permutation of
the integers |
resize |
a flag indicating whether the vector should be
resized as well as having its elements reordered (default |
keep.class |
logical indicating if the result should be of the
same class as |
... |
potential further arguments of methods. |
A transposed version of array a
, with subscripts permuted as
indicated by the array perm
. If resize
is TRUE
,
the array is reshaped as well as having its elements permuted, the
dimnames
are also permuted; if resize = FALSE
then the
returned object has the same dimensions as a
, and the dimnames
are dropped. In each case other attributes are copied from a
.
The function t
provides a faster and more convenient way of
transposing matrices.
Jonathan Rougier, J.C.Rougier@durham.ac.uk did the faster C implementation.
Becker, R. A., Chambers, J. M. and Wilks, A. R. (1988) The New S Language. Wadsworth & Brooks/Cole.
t
, to transpose matrices.
# interchange the first two subscripts on a 3-way array x
x <- array(1:24, 2:4)
xt <- aperm(x, c(2,1,3))
stopifnot(t(xt[,,2]) == x[,,2],
t(xt[,,3]) == x[,,3],
t(xt[,,4]) == x[,,4])
UCB <- aperm(UCBAdmissions, c(2,1,3))
UCB[1,,]
summary(UCB) # UCB is still a contingency table