MATLAB Central Newsreader - Trying to plot a sinc function

Trying to plot a sinc function

Yan Rosh — Mon, 15 Dec 2008 19:38:02 -0500

I have to following problem:

I define a variable t, as such: t = (-12:0.001:12);
and then I try to plot this graph:

y = sinc(t)cos(t);

but then I get an error message (unfortunately I am not in the schools computer lab so I can't tell you the exact error message), it says basically that I can't multiply those matrices because they are not of the same size.

What am I doing wrong here?

Thank you!!!

Re: Trying to plot a sinc function

Roger Stafford — Mon, 15 Dec 2008 19:55:04 -0500

"Yan Rosh" <yan_rosh@yahoo.com> wrote in message <gi6bmq$n69$1@fred.mathworks.com>...
> I have to following problem:
>
> I define a variable t, as such: t = (-12:0.001:12);
> and then I try to plot this graph:
>
> y = sinc(t)cos(t);
>
> but then I get an error message (unfortunately I am not in the schools computer lab so I can't tell you the exact error message), it says basically that I can't multiply those matrices because they are not of the same size.
>
> What am I doing wrong here?
>
> Thank you!!!

I am guessing you need to add the 'dot' along with the multiplication symbol:

y = sinc(t).*cos(t);

Roger Staffod

Re: Trying to plot a sinc function

Yan Rosh — Mon, 15 Dec 2008 20:19:02 -0500

"Roger Stafford" <ellieandrogerxyzzy@mindspring.com.invalid> wrote in message <gi6cmo$8mk$1@fred.mathworks.com>...
> "Yan Rosh" <yan_rosh@yahoo.com> wrote in message <gi6bmq$n69$1@fred.mathworks.com>...
> > I have to following problem:
> >
> > I define a variable t, as such: t = (-12:0.001:12);
> > and then I try to plot this graph:
> >
> > y = sinc(t)cos(t);
> >
> > but then I get an error message (unfortunately I am not in the schools computer lab so I can't tell you the exact error message), it says basically that I can't multiply those matrices because they are not of the same size.
> >
> > What am I doing wrong here?
> >
> > Thank you!!!
>
> I am guessing you need to add the 'dot' along with the multiplication symbol:
>
> y = sinc(t).*cos(t);
>
> Roger Staffod

Thanks, ill try it and let you know... :)

Re: Trying to plot a sinc function

chen — Tue, 16 Dec 2008 05:22:30 -0500

This error is because when you write this program in matlab like y=sinc(t)*cos(t) it's means array sinc(t) multiply array cos(t).so you should write like
y=sint(t).*cis(t) in matlab program .