NAME

Sim::OPT.

SYNOPSIS

use Sim::OPT;
opt;

DESCRIPTION

Sim::OPT is an optimization and morphing program oriented to problem decomposition that can be used with simulation programs receiving text files as input and emitting text files as output. Some of Sim::OPT's optimization modules (Sim::OPT, Sim::OPT::Descent) pursue optimization through block search, allowing blocks (subspaces) to overlap, and allowing a free intermix of sequential search approaches (inexact Gauss-Seidel method) and parallell ones (inexact Jacobi method). The Sim::OPT::Takechange module seeks for the least explored search paths when exploring new search spaces sequentially. Sim::OPT::Morph, Sim::OPT's morphing module, manipulates chosen parameters in the configuration files (constituted by text files) of models for simulation programs, recognizing variables by position. The Sim::OPT::Parcoord3d module converts 2D parallel coordinates plots in Autolisp instructions for obtaining 3D plots as Autocad drawings.

Sim::OPT's morphing and reporting modules contain several additional functions specifically targeting the ESP-r building performance simulation platform. A working knowledge of ESP-r (http://www.esru.strath.ac.uk/Programs/ESP-r.htm) is necessary to use those functionalities.

To install Sim::OPT, the command <cpanm Sim::OPT> has to be issued as a superuser. OPT can then be loaded through the command <use Sim::OPT> in a Perl repl. To ease the launch, the batch file "opt" (which can be found packed in the "optw.tar.gz" file in "examples" folder in this distribution) may be copied in a work directory and the command <opt> may be issued. That command will call OPT with the settings specified in the configuration file. When launched, Sim::OPT will ask the path to that file, which must contain a suitable description of the operations to be accomplished and point to an existing simulation model.

The "$mypath" variable in the configuration file must be set to the work directory where the base model reside.

To run the morphing functions of OPT without making OPT launch the simulation program, the setting <$exeonfiles = "n";> should be specified in the configuration file. That way the commands will only be printed to a file. This can be aimed to inspect the commands that OPT would give the simulation program.

Besides an OPT configuration file, separate configuration files for propagation of constraints may be created. Those can be useful to give the morphing operations greater flexibility. Propagation of constraints can regard the geometry of a model, solar shadings, mass/flow network, controls, and generic text files descripting a simulation model.

The simulation model folders and the result files that will be created in a parametric search will be named as the base model, plus numbers and other characters naming model instances. For example, the instance produced in the first iteration for a root model named "model" in a search constituted by 3 morphing phases and 5 iteration steps each will be named "model_1-1_2-1_3-1"; and the last one "model_1-5_2-5_3-5".

The structure of block searches is described through the variable "@sweeps" in the configuration file. Each case is listed inside square brackets. And each search subspace (block) in each case is listed inside square brakets. For example: a sequence constituted by two brute force searches, one regarding parameters 1, 2, 3 and the other regarding parameters 1, 4, 5, 7 would be described with: @sweeps = ( [ [ 1, 2, 3 ] ] , [ [ 1, 4, 5, 7 ] ] ) (1). And a sequential block search with the first subspace regarding parameters 1, 2, 3 and the second regarding parameters 3, 4, 5, 6 would be described with: @sweeps = ( [ [ 1, 2, 3 ] , [ 3, 4, 5, 6 ] ] ). That search could be made parallel by putting in front of the first subspace list the letter "p", which would signal that the search in that block and in the one following it has to be made in parallel, in sequence: ( [ [ "p", 1, 2, 3 ] , [ 3, 4, 5, 6 ] ] ) (2). The possibility of articulating a mix of parallel and sequential searches is important!, because it allows to design search structures with a depth, embodying precedence, and therefore procedural time, it them.

The number of iterations to be taken into account for each parameter for each case is specified in the "@varinumbers" variable. To specifiy that the parameters of the last example are to be tried for three values (iterations) each, @varinumbers has to be set to ( { 1 => 3, 2 => 3, 3 => 3, 4 => 3, 5 => 3, 6 => 3 } ).

The instance number that has to considered the basic one, corresponding to the root case, is specified by the variable "@miditers". "@miditers" for the last example may be for instance set to ( { 1 => 2, 2 => 2, 3 => 2, 4 => 2, 5 => 2, 6 => 2 } ).

Where Sim::OPT may be fit for a task? Where a certain exploration is complex and/or when it is to be confronted through decomposition, by dividing a problem in overlapping subproblems; when there aren't slick tools suitable to decomposition-based, simulation-based optimization; when spending a day, or two, or three setting up a model may spare months of work.

Where it may not be suitable for the task? Due to the investment which is necessary for getting acquainted with its raw interface, for quick shots at small explorations.

The program works under linux. Instructions that may allow its use under Windows have been included in the code, but have yet never been tested.

EXPORT

"opt".

SEE ALSO

Annotated examples ("esp.pl" for ESP-r, "ep.pl" for EnergyPlus - the two perform the same morphing operations on models describing the same building -, and "des.pl" about block search) can be found packed in the "optw.tar.gz" file in "examples" directory in this distribution. They constitute the available documentation. Additionally, reference to the source code may be made.

AUTHOR

Gian Luca Brunetti, <gianluca.brunetti@polimi.it>

COPYRIGHT AND LICENSE

Copyright (C) 2008-2016 by Gian Luca Brunetti and Politecnico di Milano. This 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, version 2 or later.