numeric matrix of relative weights, rows corresponding to genes and columns to arrays
status
character vector giving the control status of each spot on the array, of same length as the number of rows of weights
values
character vector giving subset of the unique values of status
multipliers
numeric vector of same length as values giving factor by which weights will be modified
Value
Numeric matrix of same dimensions as weights with rows corresponding to values in status modified by the specified multipliers.
Details
The function is usually used to temporarily modify the weights matrix during normalization of data.
The function can be used for example to give zero weight to spike-in ratio control spots during normalization.
See Also
An overview of normalization functions available in LIMMA is given in 05.Normalization.
w <- matrix(runif(6*3),6,3)
status <- c("Gene","Gene","Ratio_Control","Ratio_Control","Gene","Gene")
modifyWeights(w,status,values="Ratio_Control",multipliers=0)