Scilab

Scilab is a comprehensive, powerful and free software package for applications in numerical mathematics, the former at the Institut national de recherche en informatique et en automatique ( INRIA ) was developed in France since 1990 as an alternative to MATLAB and since 2003 by Scilab Consortium will be further developed. Since July 2008, the Scilab Consortium Member of Digiteo Foundation. Since July 2012, the publication and development carried out by Scilab Enterprises.

The functionality and syntax of Scilab / Xcos is identical to a large extent with the MATLAB / Simulink, and there are converter MATLAB by Scilab. Scilab is used among others for technical and scientific applications in teaching, research and industry. Scilab provides by itself offers functionality for the following areas available: 2D and 3D plots of all current forms on the basis of gnuplot (or / and LabPlot ), numerical linear algebra, polynomial calculations, statistics, control engineering, digital signal processing, and I / O functions for reading and writing data, including the sound files in the WAVE file format. Moreover, there exists a variety of pre - Scilab / Xcos solution scripts and function libraries of users from all over the world.

Implements 's Scilab / Xcos in C, but it is also expandable by modules that have been written in Scilab / Xcos themselves or in other languages, such as FORTRAN, Python exist with SciPy or C, for the defined interfaces. It provides defined interfaces to already available or even programmable toolkits ( toolboxes ) as Xcos, SPI, LabVIEW, Modelica, but also MuPAD. With the release of version 5.0, many graphical features and the user interface in Java have been reprogrammed.

Demarcation

Due to the virtually non-existent algebraic functions Scilab is not part of the Computer Algebra System (CAS ), such as Maxima, Maple or Mathematica that support, in contrast to purely numerical mathematics, and symbolic methods.

Add-on packages

Included with Scilab powerful additional tools are available, including:

• SciNotes, a specially developed for Scilab text editor and debugger that simplifies the editing of Scilab scripts. It supports, among other things: Highlighting the Scilab syntax
• Automatic identification of functions
• AutoComplete
• Directly Execute scripts in Scilab
• Tabbed Browsing
• Comments are rows and paragraphs
• Line numbering
• Help function

• Xcos (formerly Scicos ), a software package similar to Simulink, for graphical modeling and simulation of dynamic systems. Xcos 1.0 based on Scicos 4.2 and is fully compatible with it. Xcos contains a collection of graphic icons. These can be similar to an electronic circuit wiring together. A distinction is made between time information (red lines ) and the actual signals ( blue lines ). So created programs and block diagrams can be converted into a C program. With a suitable C compiler, the programs can then click any target platform, for example, to microcontrollers, transferred. The current Scicos version 4.4 (December 2009) is available in the co- free, based on Scilab 4.1.2 development environment ScicosLab. There is a free compiler for Modelica models available, which allows to use Modelica models directly in Scilab / Xcos and edit.

• ATOMS ( engl: Automatic Modules Management for Scilab ) enables the automatic install and update other additional program packages.

Syntax

The Scilab syntax is largely based on the MATLAB programming language. The easiest way to run Scilab statements, is this typing directly to the command prompt >> in graphical input window. In this way, Scilab can be used as an interactive mathematical shell.

Application Examples

• Arithmetic Calculations: Numerical values ​​can be stored in variables. Special constants are % i for the imaginary unit and% pi for the district number. In addition, even all known elementary functions are available.

In the example complex alternating current calculations are performed.

-> f = 100, R = 1000; C = 1e -6;   -> ZR = R; ZC = 1 / (2 *% pi * f * C * % i ); / / Complex AC resistance   -> Z = ZR ZC / / series R and C   Z =      1000 -. 1591.5494i   -> Impedance = abs (Z ) / / impedance   Impedance =      1879.6355   -> Phase = atan ( imag ( Z) / real (Z)) * 360 / (2 * pi % ) / / Phase in degrees   phase =    - 57.858092   -> Matrices: Scilab provides appropriate functions for all matrix operations. In the example, the matrix A is declared, computed with the function whose inverse inv (A) and assigned to the variable B. The multiplication of the two matrices yields the identity matrix.

-> A = [0 1; 2 4 ]   A =  ! 0 1!  ! 2 4!   -> B = inv (A ) / / Inverse   B =  ! - 2 .5!  ! 1 0!   -> A * B   ans =  ! 1 0!  ! 0 1!   -> literature

• Stephen Campbell, Jean -Philippe Chancelier and Ramine Nikoukhahm: Modeling and Simulation in Scilab / Scicos, Springer Verlag Berlin, 1st Edition, November 2005, English, ISBN 0-387-27802-8, ISBN 978-0-387-27802 - 5 The 2nd edition of 22 December 2009 also takes into account the integration of Modelica models, ISBN 1441955267, ISBN 978-1441955265
• Claude Gomez, Casey Bunks, Jean- Philipe Chancelior and Francois Delebecque: Engineering and Scientific Computing with SciLab, with software package Scilab / Scicos and all examples on CD- ROM, Birkhauser Verlag AG, 1st Edition, 1999, English, ISBN 3 - 7643-4009-6, ISBN 978-3-7643-4009-4
• Wolfgang Polifke Jan Kopitz: Heat transfer. Foundations, analytical and numerical methods with software package Scilab / Scicos and all examples on CD- ROM. Pearson Education, Inc. Publishing, 1st Edition, January 2005, German, ISBN 3- 8273-7104 -X, ISBN 978-3-8273-7104-1
• Jean -Marie Zogg: Working with Scilab and Scicos ( Scilab for numerical computations, Scicos graphical simulations), HTW -Verlag 5/2007, 125 pages, German, free download at http://www.zogg-jm.ch/weitere_publikationen. html
• Peter Beater: control technology and simulation technology with Scilab and Modelica: An example -oriented introduction for students and users, Books on Demand, 1st Edition, January 7, 2010 German, ISBN 3837050106, ISBN 978-3837050103