What are some alternatives?
When comparing MATLAB and Scilab, you can also consider the following products
Wolfram Mathematica - Mathematica has characterized the cutting edge in specialized processing—and gave the chief calculation environment to a large number of pioneers, instructors, understudies, and others around the globe.
GNU Octave - GNU Octave is a programming language for scientific computing.
Enterprise Architect - Enterprise Architect - UML Design Tools and UML CASE tools for software development | Sparx Systems
COMSOL Multiphysics - COMSOL is the developer of COMSOL Multiphysics software, an interactive environment for modeling and simulating scientific and engineering problems.
OpenFOAM - OpenFOAM® - Official home of The Open Source Computational Fluid Dynamics (CFD) Toolbox.
Autodesk Fusion 360 - Integrated CAD, CAM, and CAE featuring collaborative editing and cloud-based computation.