I always use Matlab. There's so many options that I don't know it is advantage or disadvantage of this packet. I got used to it. The main advantage is available eps, png etc formats. What you usually use? The comments are welcome.
* Image Processing Toolbox. The Image Processing Toolbox builds on MATLAB's numeric, signal processing, and visualization capabilities to provide a comprehensive system for image processing and algorithm development.
* Model Predictive Control Toolbox. The Model Predictive Control Toolbox is especially useful for applications involving constraints on the manipulated and/or controlled variables. For unconstrained problems, model predictive control is closely related to linear quadratic optimal control, but includes modeling and tuning options that simplify the design procedure.
* Nonlinear Control Design. This toolbox provides a Graphical User Interface to assist in time-domain-based control design. With this toolbox, you can tune parameters within a nonlinear SIMULINK model to meet time-domain performance requirements. You can view the progress of an optimization while it is running. Optimization routines have been taken from the Optimization Toolbox.
* Robust Control Toolbox. This is a toolbox for robust control system design and supports LQG/loop transfer recovery, H2, H0, and mu- control synthesis, singular value frequency response, and model reduction.
* Signal Processing Toolbox. This is a toolbox for digital signal processing (time series analysis). It includes functions for the design and analysis of digital filters, like Butterworth, Elliptic, and Parks-McClellan, and for FFT analysis (power spectrum estimation). It also includes some two-dimensional signal processing capabilities.
* Statistics Toolbox. The Statistics Toolbox builds on the computational and graphics capabilities of MATLAB to provide: 1) statistical data analysis, modeling, and Monte Carlo simulation 2) building blocks for creating your own special-purpose statistical tools, and 3) GUI tools for exploring fundamental concepts in statistics and probability.
* System Identification Toolbox. This is a toolbox for parametric modeling. Identified models are in transfer function form (either z transform or Laplace transform) and state-space form (e.g., ARMA models or Box-Jenkins models).
Thank you all for your comments. I attach examples of my figures, which are made in Matlab. Could you attach your examples then it will be very easy to compare, what offer software packages.
I always avoid graphs from excel. It is not only my opinion as we can see above. Are you sure that Excel has an option to generate three dimensional graphs
I usually work with a combination of Excel (descriptive statistics, preparation) and Visio (Windows)/Omnigraffle (MacOSX). Both Visio and Omnigraffle are easier to use as Illustrator and are normally sufficient for academic purposes. These programs generate vector-based figures that are scalable and cause no problems with printing...
Personally, I very like graphics made by LaTeX classes (e.g. tikz). Unfortunately, I never found an enough clear tutorial to learn it. Sometimes, I make only a simple graphics by using LaTex.