version 1.2.0.0 (15.3 KB) by
Henry Harrison

GUI that plots dynamical system flow fields (and more) with sliders for adjusting parameters.

sysViewer Dynamical system graphical interface.

h = sysViewer(oPar, cPar, fcn, typ) builds a GUI for viewing the

effects of parameter changes on a one- or two-dimensional dynamical

system.

oPar and cPar are two-column cell arrays that define the order

parameter and control parameter(s), respectively. The first column

contains parameter names (strings to be typeset in latex). The second

column contains 1x2 vectors of parameter's range. This vector defines

plot axes limits for the order parameter and slider limits for the

control parameters.

The system is defined by the function handle fcn. For one-dimensional

systems, this should be a function with two inputs and one output. The

first input is system state, which will be a scalar in a one-

dimensional system. The second input is a vector of control parameter

values. The output of fcn can be either the rate of change of the order

parameter (in which case fcn is the flow equation), or the system

potential (in which case fcn is the potential function). Which function

is supplied can be indicated by the last input typ, one of the strings

'flow' or 'potential'. If typ is empty or omitted, 'flow' is the

default.

For two-dimensional systems defined with a flow, fcn should be a cell

array containing two function handles, each outputting the rate of

change along one dimension. Each function should take three inputs; the

first two are scalar values of the order parameters, the third is a

vector of control parameters. For two-dimensional systems defined with

a potential, fcn should take inputs as above and output a scalar.

The output h is a struct containing handles to the graphics objects in

the GUI. Intended only for advanced tweaking or troubleshooting.

sysViewer(..., defs) initializes the parameter sliders with the default

values in vector defs.

sysViewer(..., 'vectorize') speeds up computation for functions that

cannot be evaluated with a vector. In fact, any number of trailing

arguments will be passed to chebfun. See CHEBFUN for more options

(CHEBFUN2 and CHEBFUN2V for two-dimensional options).

--------

Examples:

------

One-dimensional

---

sysViewer({'\phi' [-pi pi]}, ...

{'b/a' [0 1]; '\Delta\omega' [-2 2]}, ...

@(x,c) c(2)*x-cos(x)-c(1)*cos(2*x), ...

'potential');

sysViewer({'\phi' [-pi pi]}, ...

{'b/a' [0 1]; '\Delta\omega' [-2 2]}, ...

@(x,c) c(2)-sin(x)-2*c(1)*sin(2*x), ...

'flow');

sysViewer({'\phi' [-pi pi]}, ...

{'b/a' [0 1]; '\Delta\omega' [-2 2]; 'c' [0 .5]; 'd' [0 .5]}, ...

@(x,c) c(2)*x-cos(x)-c(1)*cos(2*x)+c(3)*sin(x)+c(4)*sin(2*x), ...

'potential');

sysViewer({'\phi' [-pi pi]}, ...

{'b/a' [0 1]; '\Delta\omega' [-2 2]; 'c' [0 .5]; 'd' [0 .5]}, ...

@(x,c) c(2)-sin(x)-2*c(1)*sin(2*x)+c(3)*cos(x)+2*c(4)*cos(2*x), ...

'flow');

------

Two-dimensional

---

sysViewer('x' [-5 5]; '\dot{x}' [-5 5]}, ...

[{'\alpha'; '\beta'; '\delta'} repmat({[-5 5]}, 3, 1)], ...

{@(x,dx,r) dx, @(x,dx,r) -r(1).*x.^3 - r(2).*x - r(3).*dx}, ...

'flow')

--------

Dependencies (if missing, user will be prompted to download and install):

GUI Layout Toolbox

sliderPanel

uibutton

Chebfun:

- Stable version (one-dimensional systems only)

- Alpha release (required for viewing two-dimensional systems)

(as of March 14 2013)

Henry Harrison (2020). Dynamical System Viewer (https://www.mathworks.com/matlabcentral/fileexchange/40812-dynamical-system-viewer), MATLAB Central File Exchange. Retrieved .

Created with
R2012b

Compatible with any release

**Inspired by:**
uibutton: GUI pushbuttons with better labels, sliderPanel, Chebfun V4 - old version; please download current version instead, GUI Layout Toolbox, Require FEX package

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Henry HarrisonAdam, thanks for the feedback.

Yep, it was working through Strogatz (and my professor's terrible Matlab visualizations) that inspired me to write this.

I had removed the toolbars at one point but I added them back in for some reason. Don't remember what my reason was, if I can remember which tool I needed maybe I'll delete the rest but leave that.

I'll definitely go with OOP next time, especially after learning OOP design principles for Python. It definitely looks easier for Matlab GUIs.

Thanks for the addlistener tip! That always bugged me.

Adam FilionCool tool, wish I had this back in grad school when I was working through Nonlinear Dynamics and Chaos by Strogatz. I have a few suggestions.

- Personally, I find it much easier to build and maintain apps in MATLAB as handle classes rather than through purely functional programming. You can find an article introducing the idea and why it should be used here:

http://www.mathworks.com/company/newsletters/articles/writing-apps-in-matlab.html

- Remove any menus or toolbar buttons you don’t want users playing with. There’s no reason to use things like the 3D rotate tool with this app. For example, you can remove all of them with:

menus = findall(gcf,'Type','uimenu');

delete(menus)

toolbar = findall(gcf,'Type','uitoolbar');

delete(toolbar)

- Try using addlistener to create continuous feedback when dragging sliders, something like the following has worked well for me.

myslider = uicontrol('Style', 'slider', 'Callback', @sliderCB);

addlistener(myslider,'ContinuousValueChange',@sliderCB);

- There's a small typo in two dimension example, missing a {

Henry HarrisonI'm open for suggestions for useful features.