Simplot Command

From ControlTheoryPro.com

Jump to: navigation, search
Symbol.gif
Simplot Command
Green carrot left.gif
All MATLAB Articles MATLAB's Plot Command
Green carrot.jpg
In order to prevent spam, users must register before they can edit or create articles.

1 Introduction

The simplot command is used to plot Simulink model output data. When using simplot with saved Scope data (using the Struture with Time option) simplot will plot the Simulink data in the same form as would be displayed by the scope. This includes plotting the data with signal labels.

2 Basic Simplot

The most basic way to use simplot is to use simplot on data saved by a Scope block. Scope data can be plotted with the following comand

 >> simplot(data);

The data to be plotted can be either a data structure or a matrix of the form produced by Simulink output blocks.

2.1 Time & Data

If the data is in separate time and data vectors than it can be plotted via simplot using the command below.

 >> simplot(time, data);

2.2 Structure with Time

When saving data using a scope block there are a couple of options for saving that data. One of those options is the Structure with Time. The Structure with Time option saves the data to a structure with time, signal labels, and other useful information from the Simulink model.

3 Specifying Ports

The data can be saved using several standard blocks. When the data is a structure produced by a Scope block with multiple ports, the data from each port is displayed in a separate subplot. Specific ports can be selected for display by supplying a vector of port indices.

 >> ports = [1,3];
 >> simplot(data,ports)

4 Comparing Runs

There are a number of reasons for comparing the results of multiple simulation runs. Trade studies and answering proposal questions common reasons for comparing the results of one simulation run to another. The following subheadings detail two uses.

4.1 Overlay plots

With multiple data runs the data needs to be saved to a cell array. The cell array of data structure (Structure with Time) is processed by the simplot command.

 >> data = {run1, run2};
 >> simplot(data)

This command will overlay the results data from multiple simulation runs.

4.2 Difference between runs

Using simplot as below, MATLAB uses it to compare every run to the first run.

 >> data = {run1, run2};
 >> simplot(data, 'diff')