Thread Subject:

How to find Convolution integral using Symbolic Math Toolbox ?

I already have a code to convolve two signals using 'conv' & 'conv2'.
But I was asked to do that using Symbolic Math Toolbox !!!!!
I cannot understand how to begin even though I checked out a few tuts on the internet !!!
Please Help !!!!
The question is :
x (t) = exp(-3t) * u (t),
h (t) = u (t + 3)

On 21 Feb., 10:22, "Animesh Pandey" <apanimesh...@gmail.com> wrote:
> I already have a code to convolve two signals using 'conv' & 'conv2'.
> But I was asked to do that using Symbolic Math Toolbox !!!!!
> I cannot understand how to begin even though I checked out a few tuts on the internet !!!
> Please Help !!!!
> The question is :
> x (t) = exp(-3t) * u (t),
> h (t) = u (t + 3)

By using the 'int' - command ?

Best wishes
Torsten.

On 2/21/2011 1:22 AM, Animesh Pandey wrote:
> I already have a code to convolve two signals using 'conv'& 'conv2'.
> But I was asked to do that using Symbolic Math Toolbox !!!!!
> I cannot understand how to begin even though I checked out a few tuts on the internet !!!
> Please Help !!!!
> The question is :
> x (t) = exp(-3t) * u (t),
> h (t) = u (t + 3)

Well, here is the answer using Mathematica:


In[21]:= f[x_]:=Exp[-3 x] UnitStep[x]
g[x_]:= UnitStep[x+3]

Integrate[f[t-x]*g[x],{x,-Infinity,Infinity}]

Out[23]= 1/3 (1-E^(-3 (3+t))) UnitStep[3+t]

Now, simply translate the above using Matlab
symbolic tool commands. This is left as an exercise
for you. help syms and help int()

--Nasser