Description Usage Arguments Details Value Author(s) See Also Examples
statList
provides a general method for calculating univariate or
multivariate statistics for a matrix or data.frame stratified by one
or more factors.
1 2 3 4 5 |
X |
A matrix or data frame containing the variables to be summarized |
factors |
A vector, matrix or data frame containing the factors for which
|
FUN |
A function to be applied to the pieces of |
drop |
Logical, indicating whether empty levels of |
... |
Other arguments, passed to |
statList
is the general function.
X
is first split
by factors
, and FUN
is applied to the result.
colMeansList
and covList
are just calls to
statList
with the appropriate FUN
.
Returns a list of items corresponding to the unique elements in
factors
, or the interaction of factors
.
Each item is the result of applying FUN
to that
collection of rows of X
.
The items are named according to the levels in factors
.
Michael Friendly
1 2 3 4 5 6 7 8 9 10 11 12 13 | # grand means
statList(iris[,1:4], FUN=colMeans)
# species means
statList(iris[,1:4], iris$Species, FUN=colMeans)
# same
colMeansList(iris[,1:4], iris$Species)
# var-cov matrices, by species
covList(iris[,1:4], iris$Species)
# multiple factors
iris$Dummy <- sample(c("Hi","Lo"),150, replace=TRUE)
colMeansList(iris[,1:4], iris[,5:6])
|
Add the following code to your website.
For more information on customizing the embed code, read Embedding Snippets.