Package: PTAk
Version: 1.1-1
Date: 2001/04/17
Title: Principal Tensor Analysis on k modes
Author: Didier Leibovici <didier@fmrib.ox.ac.uk>.
Depends: tensor (useful but not necessary)
Description: A multiway method to decompose a tensor (array) of any order,
             as a generalisation of SVD also supporting \emph{non-identity metrics} and \emph{penalisations}.
             2-way SVD with these extensions is also available. The package includes also some other multiway
             methods: PCAn (Tucker-n) and PARAFAC/CANDECOMP.
License: free for non-commercial purposes.
Maintainer: Didier Leibovici <didier@fmrib.ox.ac.uk>.
URL: http://www.fmrib.ox.ac.uk/~didier

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 Copyright (C) 2000 Didier Leibovici

  The main Reference to quote
        check also  http://www.fmrib.ox.ac.uk/~didier/cv/recentpub.html

 Leibovici D and Sabatier R (1998)
   "A Singular Value Decomposition of a k-ways array for a
 Principal Component Analysis of multi-way data, the PTA-k"
                          Linear Algebra and its Applications
                                  269:307-329.
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2001/02/22
If one does not want to use the tensor package the default arguments of CONTRACTION
and CONTRACTION.list has to be change with usetensor=FALSE.

Some C++ code are currently developed  to speed the core algorithms.
 #
2001/04/17
 smoothing option allows different smoothing for different Principal Tensors.
