The S4Vectors package defines aggregate
methods
for Vector, Rle, and List objects.
1 2 3 4 5 6 7 8 9 10 11  ## S4 method for signature 'Vector'
aggregate(x, by, FUN, start=NULL, end=NULL, width=NULL,
frequency=NULL, delta=NULL, ..., simplify=TRUE)
## S4 method for signature 'Rle'
aggregate(x, by, FUN, start=NULL, end=NULL, width=NULL,
frequency=NULL, delta=NULL, ..., simplify=TRUE)
## S4 method for signature 'List'
aggregate(x, by, FUN, start=NULL, end=NULL, width=NULL,
frequency=NULL, delta=NULL, ..., simplify=TRUE)

x 
A Vector, Rle, or List object. 
by 
An object with If 
FUN 
The function, found via 
start, end, width 
The start, end, and width of the subsets. If 
frequency, delta 
Optional arguments that specify the sampling frequency and increment
within the subsets (in the same fashion as 
... 
Optional arguments to 
simplify 
A logical value specifying whether the result should be simplified to a vector or matrix if possible. 
Subsets of x
can be specified either via the by
argument
or via the start
, end
, width
, frequency
, and
delta
arguments.
For example, if start
and end
are specified, then:
1 
is equivalent to:
1 2 
(replace x[start[i]:end[i]]
with 2Dstyle subsetting
x[start[i]:end[i], ]
if x
is a DataFrame object).
The aggregate
function in the stats
package.
Vector, Rle, List, and DataFrame objects.
The start
,
end
, and
width
generic functions defined in
the BiocGenerics package.
1 2 3 4 5 6 7 8 9 10 11 12  x < Rle(10:2, 1:9)
aggregate(x, x > 4, mean)
aggregate(x, FUN=mean, start=1:26, width=20)
## Note that aggregate() works on a DataFrame object the same way it
## works on an ordinary data frame:
aggregate(DataFrame(state.x77), list(Region=state.region), mean)
aggregate(weight ~ feed, data=DataFrame(chickwts), mean)
library(IRanges)
by < IRanges(start=1:26, width=20, names=LETTERS)
aggregate(x, by, is.unsorted)

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