## The module "multi2colblocks" of the Mastrave modelling library

Daniele de Rigo

The file multi2colblocks.m is part of Mastrave.

Mastrave is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.

Mastrave is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License along with Mastrave. If not, see http://www.gnu.org/licenses/.

#### Function declaration

[col_blocks, n_dims, n_points] = ...
multi2colblocks( values                      ,
dims            = []        ,
points          = []        ,
in_orientation  = 'columns' ,
out_orientation = 'columns' )



#### Description

Utility for extracting from a given dataset values (a matrix or multi-dimensional array) a sequence of subsets. values is intended to be a collection of N multidimensional points (or layers). If in_orientations has the default value, each column of values is intended to contain N values corresponding to a given coordinate of N points (or layers). From values , a sequence of blocks of coordinates - by default a sequence of sub-sets of columns - is to be aggregated in col_blocks . Each block is composed by the N points (or by the number of points indicated by points ) whose non-selected coordinates are replaced with zeros. In case values were a multidimensional array, the position of each coordinate dimension is equivalent to the position of the corresponding column in the matrix returned by multi2mat( values , in_orientation ).

#### Input arguments


values            ::numeric::
Numeric vector, matrix or multidimensional-array.  It is
intended to be a collection of N multidimensional points
(or layers): if  in_orientations  has the default value,
each column of  values  is intended to contain N values
corresponding to a given coordinate of N points (or
layers).  From  values , a sequence of blocks of
coordinates ─ by default a sequence of sub-sets of
columns ─ is to be aggregated in  col_blocks .  Each
block is composed by the N points (or by the number of
points indicated by  points ) whose non-selected
coordinates are replaced with zeros.

dims              ::cellindex::
Cell-array of dimension sets (or just a single dimension
set) the i-th of them lists which of the n dimensions of
values  (e.g. which of its n columns, if  in_orientation
has the default value) need to be preserved in the i-th
block to be returned within  col_blocks .
In case  values  were a multidimensional array, the
position of each coordinate dimension is equivalent to
the position of the corresponding column in the matrix
returned by  multi2mat(  values ,  in_orientation  ).
if  dims  is an empty matrix [], all dimensions will be
separately included, so that [] is considered equivalent
{ 1, 2, ... , n }.
If omitted, the default value is an empty matrix: [].

points            ::cellindex-1|numel::
Cell-array of indexes to the points of  values  (e.g.
its rows, if  in_orientation  has the default value)
to which each block element belongs.
The i-th array of indexes of the cell-array  points
refers to the points of  values  to be included within
the i-th block of  col_blocks .  The dimensions of
these points which are listed in the i-th array of
dims  will be included in the i-th block of
col_blocks .
The values of the omitted dimensions of the points
will be replaced with zeros.
If a vector of non-negative numbers is passed instead
of a cell-array, the i-th element of it is expected to
indicate the number of points of  values  (starting
from the first point) to be included in the i-th block
of  col_blocks .
if  points  is an empty matrix [], all points will be
included.
If omitted, the default value is an empty matrix: [].

in_orientation    ::scalar_index|string::
Dimension along which to split  values  into blocks
(default: 'columns').  Each  colbloks  column
corresponds to a coordinate along the specified
dimension of  values .
In case a string is passed, valid options are:

option      │   meaning
───────────────┼─────────────────────────────────────
'columns'   │ Split  values  dimensions by
│ considering them column-wise (each
│ dimension corresponds to a column).
│ Equivalent to 1. (Default value).
───────────────┼─────────────────────────────────────
'rows'      │ Split  values  dimensions by
│ considering them row-wise (each
│ dimension corresponds to a row).
│ Equivalent to 2.

out_orientation   ::scalar_index|string::
Dimension along which the blocks of  values  are to be
packed in the sparse matrix  col_blocks
(default: 'columns').
In case a string is passed, valid options are:

option      │   meaning
───────────────┼─────────────────────────────────────
'columns'   │ Pack  values  blocks so that each
│ dimension corresponds to a column
│ (column-wise).
│ Equivalent to 1. (Default value).
───────────────┼─────────────────────────────────────
'rows'      │ Pack  values  blocks so that each
│ dimension corresponds to a row
│ (row-wise).
│ Equivalent to 2.



#### Example of usage

See also:
multi2mat, mat2multi, cell2sparse, mdeal

Keywords:
multidimensional-array, smart reshape, column-wise, row-wise

Version: 0.7.2

#### Support

The Mastrave modelling library is committed to provide reusable and general - but also robust and scalable - modules for research modellers dealing with computational science.  You can help the Mastrave project by providing feedbacks on unexpected behaviours of this module.  Despite all efforts, all of us - either developers or users - (should) know that errors are unavoidable.  However, the free software paradigm successfully highlights that scientific knowledge freedom also implies an impressive opportunity for collectively evolve the tools and ideas upon which our daily work is based.  Reporting a problem that you found using Mastrave may help the developer team to find a possible bug.  Please, be aware that Mastrave is entirely based on voluntary efforts: in order for your help to be as effective as possible, please read carefully the section on reporting problems.  Thank you for your collaboration.

Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013, 2014, 2015, 2016 Daniele de Rigo