# Matlab symbollic toolbox help

1. Mar 11, 2009

### eugenius

Hello, I have an assignment that requires the use of matlab. Basically I'm going to be solving circuits in the laplace domain. The professor wants us to learn matlab because apparently real engineers use it.

I own matlab r2008a. I have no clue if it has the symbollic math toolbox or not, but I know that its having trouble understanding the script I'm supposed to use for this assignment.

Here is the script. If anyone has any clue what functions those are, and where the heck I'm supposed to get the symbolic toolbox that can read this script, please tell me.

Code (Text):
% Unit-step function
u=sym('Heaviside(t)')
U=laplace(u)
pause

% Delta function
d=sym('Dirac(t)')
D=laplace(d)
pause

%exponential
e=sym('exp(-2*t)')
ezplot(e,[0,10])
axis([0 10 0 1.1])
grid
pause
E=laplace(e)

% decaying cosine
f=e*sym('cos(10*t)')
ezplot(f,[0,5])
axis([0 5 -1 1])
grid
pause
F=laplace(f);
pretty(F)

g=sym('Heaviside(t-2)');
G=laplace(g)
pretty(G)
pause

2. Mar 11, 2009

### MATLABdude

To see which toolboxes you have installed, try using the MATLAB launch pad (go to the View menu and then make sure the Launch Pad is checked). If there's no Symbolic Math Toolbox in the launch pad, then you don't have it installed. You can also use the 'demo' command to bring up the demo control panel and see which toolboxes are installed.

Each of the toolboxes (for student use) is \$59 from the Mathworks store. If your professor is expecting you to use the Symbolic Toolbox, I'd fire off an e-mail asking if there's a computer lab somewhere on your campus where that's installed (chances are good). As to what the various functions do, the absolute easiest way to get documentation is to fire up MATLAB and type in help <name of function> for instance:

>> help ezplot

You can also look at the (more detailed) online MATLAB documentation:
http://www.mathworks.com/access/helpdesk/help/techdoc/ref/funcalpha.html [Broken]

There's also the documentation for each of the toolboxes:
http://www.mathworks.com/access/helpdesk/help/helpdesk.html

Last edited by a moderator: May 4, 2017
3. Mar 12, 2009

### eugenius

Thank you, it seems my problem was that I have Windows 64 bit and symbolic toolbox doesnt work with 64 bit. I tried 32 bit and it works.