Delete the dimensions of an array which have only one level.
Usage
drop(x)
Arguments
x
an array (including a matrix).
Value
If x is an object with a dim attribute (e.g., a matrix
or array), then drop returns an object like
x, but with any extents of length one removed. Any
accompanying dimnames attribute is adjusted and returned with
x: if the result is a vector the names are taken from
the dimnames (if any). If the result is a length-one vector,
the names are taken from the first dimension with a dimname.
Array subsetting ([) performs this reduction unless used
with drop = FALSE, but sometimes it is useful to invoke
drop directly.