Multiplies genes (columns) in given expression data such that their correlation with given reference vector is non-negative.
alignExpr(datExpr, y = NULL)A data frame containing the aligned expression data, of the same dimensions as the input data frame.
expression data to be aligned. A data frame with columns corresponding to genes and rows to samples.
reference vector of length equal the number of samples (rows) in datExpr
Steve Horvath and Peter Langfelder
The function basically multiplies each column in datExpr by the sign of its correlation with
y. If y is not given, the first column in datExpr will be used as the reference
vector.