\HeaderA{normalizeMedianAbsValues}{Normalize Columns of a Matrix to have the Median Absolute Value}{normalizeMedianAbsValues}
\keyword{array}{normalizeMedianAbsValues}
\begin{Description}\relax
Performs scale normalization of an M-value matrix or an A-value matrix across a series of arrays.
Users do not normally need to call these functions directly - use \code{normalizeBetweenArrays} instead.
\end{Description}
\begin{Usage}
\begin{verbatim}
normalizeMedianAbsValues(x)
\end{verbatim}
\end{Usage}
\begin{Arguments}
\begin{ldescription}
\item[\code{x}] numeric matrix
\end{ldescription}
\end{Arguments}
\begin{Details}\relax
If \code{x} is a matrix of log-ratios of expression (M-values) then \code{normalizeMedianAbsValues} is very similar to scaling to equalize the median absolute deviation (MAD) as in Yang et al (2001, 2002).
Here the median-absolute value is used for preference to as to not re-center the M-values.

\code{normalizeMedianAbsValues} is also used to scale the A-values when scale-normalization is applied to an \code{MAList} object.
\end{Details}
\begin{Value}
A numeric matrix of the same size as that input which has been scaled so that each column as the same median-absolute value.
\end{Value}
\begin{Author}\relax
Gordon Smyth
\end{Author}
\begin{SeeAlso}\relax
An overview of LIMMA functions for normalization is given in \LinkA{05.Normalization}{05.Normalization}.
\end{SeeAlso}
\begin{Examples}
\begin{ExampleCode}
M <- cbind(Array1=rnorm(10),Array2=2*rnorm(10))
normalizeMedianAbsValues(M)
\end{ExampleCode}
\end{Examples}