Usage
## S3 method for class 'array}(x, ..., drop=FALSE, indices=list(...))':
extractundefined
- x
{An array
or a matrix
.}
- ...
{These arguments are by default put into the
indices
list
.}
- indices
{A list
of index vector
s to be extracted.
The names (coerced to integers) of the list elements are the
dimension indices for each of the index vectors.}
- drop
{If TRUE
, dimensions of length one are dropped,
otherwise not.}
Returns an array
.
cat("\nCreatean array 'x' with a random number of dimensions:
")
maxdim <- 4
dim <- sample(3:maxdim, size=sample(2:maxdim, size=1), replace=TRUE)
ndim <- length(dim)
dimnames <- list()
for (kk in 1:ndim)
dimnames[[kk]] <- sprintf("%s%d", letters[kk], 1:dim[kk])
x <- 1:prod(dim)
x <- array(x, dim=dim, dimnames=dimnames)
cat("\nArray'x':
")
print(x)
cat("\nExtract'x[2:3,...]':
")
print(extract(x, "1"=2:3))
cat("\nExtract'x[3,2:3,...]':
")
print(extract(x, "1"=3,"2"=2:3))
cat("\nExtract'x[...,2:3]':
")
indices <- list(2:3)
names(indices) <- length(dim(x))
print(extract(x, indices=indices))
[object Object]
slice.index
()
methods
programming