3. Graphical Data Analysis

Visualizing data is critical to understanding it. What does a function, \(f(x)\), do when \(x\) is near zero or very large? Are there any discontinuities? Where does \(f(x)\) cross the \(x\) axis? If the data is stochastic, are there any outliers? Do we know enough about our data to make data-driven decisions? We need to make effective two and three-dimensional data plots so that we and others can understand the data.

We made several simple plots in MATLAB Programming to learn about the features of MATLAB. Here we direct our attention specifically to plotting. Remember that MATLAB has a large variety of plotting options, so we can only cover the essentials of plotting.

Resources from MathWorks

MathWorks’ website has a lot of documentation and videos related to plotting. Some recommendations follow.

• Video demonstrating how to use the Plot Tool [PlotToolVideo].

• An introductory video on how to use basic plotting functions [PlottingVideo].

• Documentation on how to create 2-D line plots [LinePlots].

• Documentation on 2-D and 3-D plots [Plots23D].

• Documentation on properties of plot lines [LineProps].

• MathWork’s MATLAB Fundamentals course has a good introduction to creating plots [FUNDAMENTALS].

Contents:

• 3.1. Interactive Plot Editing
• 3.2. Basic Line Plots
  • 3.2.1. Basic Plotting Notes
  • 3.2.2. Annotating Plots
  • 3.2.3. Starting a New Plot
  • 3.2.4. Multiple Plots in the Same Figure
  • 3.2.5. Multiple Plots on the Same Axis
  • 3.2.6. Adding a Plot Legend
  • 3.2.7. 2-D Plot Types
  • 3.2.8. Axis Control
  • 3.2.9. Tick Marks and Labels
• 3.3. Fplots
• 3.4. 3-D Plots
  • 3.4.1. 3-D Plot Functions
  • 3.4.2. Axis Orientation