| wapply {multtest} | R Documentation |
A function to perform 'apply' on an matrix of data and corresponding matrix of weights.
wapply(X, MARGIN, FUN, W = NULL, ...)
X |
A matrix of data. |
MARGIN |
A vector giving the subscripts which the function will be applied over. 1 indicates rows, 2 indicates columns. |
FUN |
The function to be applied. In the case of functions like
|
W |
An optional matrix of weights. When |
... |
optional arguments to |
When weights are provided, these are passed to FUN along with the data X. For example, if FUN=meanX, each data value is multiplied by the corresponding weight before the mean is applied.
If each call to FUN returns a vector of length n, then wapply returns an array of dimension c(n, dim(X)[MARGIN]) if n > 1. If n = 1, wapply returns a vector if MARGIN has length 1 and an array of dimension dim(X)[MARGIN] otherwise. If n = 0, the result has length 0 but not necessarily the "correct" dimension.
If the calls to FUN return vectors of different lengths, wapply returns a list of length dim(X)[MARGIN].
This function is used in the package multtest to compute weighted versions of test statistics. It is called by the function get.Tn inside the user-level function MTP.
Katherine S. Pollard
data<-matrix(rnorm(200),nr=20) weights<-matrix(rexp(200,rate=0.1),nr=20) wapply(X=data,MARGIN=1,FUN=mean,W=weights)