Thread Subject: time to frequency

hello everyone
I have a very minor problem I have a plot of amplitude versus time
amp=[-0.015 0.059 0.063 -0.02 -0.088 -0.005 0.029 0.02 -0.024 0.015]
t=linspace(0,1,10)
figure(1);plot(t,amp)
xlabel('time (s) ')
ylabel('amplitude')
How can i change the plot to an amplitude versus frequency
thanks in advance

"halee Rustumani" <halee89@hotmail.com> wrote in message <hhmlf6$138$1@fred.mathworks.com>...
> hello everyone
> I have a very minor problem I have a plot of amplitude versus time
> amp=[-0.015 0.059 0.063 -0.02 -0.088 -0.005 0.029 0.02 -0.024 0.015]
> t=linspace(0,1,10)
> figure(1);plot(t,amp)
> xlabel('time (s) ')
> ylabel('amplitude')
> How can i change the plot to an amplitude versus frequency
> thanks in advance

Suggest to use the Fourier Transform with Matlab fft. Do a search for fft in this newsgroup and you will find many comments and examples, including under my name.
Regards! Matt

"Matt Fetterman" <mattinjersey@yahoo.com> wrote in message <hhmn1r$7sa$1@fred.mathworks.com>...
> "halee Rustumani" <halee89@hotmail.com> wrote in message <hhmlf6$138$1@fred.mathworks.com>...
> > hello everyone
> > I have a very minor problem I have a plot of amplitude versus time
> > amp=[-0.015 0.059 0.063 -0.02 -0.088 -0.005 0.029 0.02 -0.024 0.015]
> > t=linspace(0,1,10)
> > figure(1);plot(t,amp)
> > xlabel('time (s) ')
> > ylabel('amplitude')
> > How can i change the plot to an amplitude versus frequency
> > thanks in advance
>
> Suggest to use the Fourier Transform with Matlab fft. Do a search for fft in this newsgroup and you will find many comments and examples, including under my name.
> Regards! Matt
------------------------------------------------
Thanks alot Matt but I dont have time to search it i just need a quick solution and as I heard it just something very minor that doesnt need alot of thinking I think its a built in function FFT just like you said but I need to know how it works
thanks

>> abs( fft(yourTimeSignal, desiredLength));

but why not a quick search for

>> help fft ???

"halee Rustumani"
> Thanks alot Matt but I dont have time to search it i just need a quick solution and as I heard it just something very minor that doesnt need alot of thinking I think its a built in function FFT just like you said but I need to know how it works
> thanks

a hint:
- look at cleve moler's nice fft exposee

http://www.mathworks.com/moler/chapters.html

us

On Jan 2, 3:24 am, "halee Rustumani" <hale...@hotmail.com> wrote:
> Thanks alot Matt but I dont have time to search it i just need a quick solution
> [snip]
> thanks
------------------------------------------------------------
But you'd have time to sit and wait an unknown length of time while
Matt or someone else does it for you???? What would you be doing
during that time?

ImageAnalyst <imageanalyst@mailinator.com> wrote in message <97d8aa14-b9bf-42ad-85be-16b4624d8990@a21g2000yqc.googlegroups.com>...
> On Jan 2, 3:24 am, "halee Rustumani" <hale...@hotmail.com> wrote:
> > Thanks alot Matt but I dont have time to search it i just need a quick solution
> > [snip]
> > thanks
> ------------------------------------------------------------
> But you'd have time to sit and wait an unknown length of time while
> Matt or someone else does it for you???? What would you be doing
> during that time?
--------------------------------------------------------------
Thanx a lot Image Analyst for your sweet words it seems that to some ppl knowledge means arrogance just a hint for ur future don’t ever judge ppl while you don’t know what there really going through you don’t even know me!!!!
I won’t say more than god forgive you.

ImageAnalyst <imageanalyst@mailinator.com> wrote in message <97d8aa14-b9bf-42ad-85be-16b4624d8990@a21g2000yqc.googlegroups.com>...
> On Jan 2, 3:24 am, "halee Rustumani" <hale...@hotmail.com> wrote:
> > Thanks alot Matt but I dont have time to search it i just need a quick solution
> > [snip]
> > thanks
> ------------------------------------------------------------
> But you'd have time to sit and wait an unknown length of time while
> Matt or someone else does it for you???? What would you be doing
> during that time?

Sometimes this newsgroup is very funny ! Someone who asks a question but doesn't have the time to actually look for the answer? "Oh sorry, I'll be on the next plane over so I can personally deliver you the answer. I know you are a very busy person !"
Or someone who asks a question about chili peppers. "Oh yes, I happen to have a chli pepper algorithm for you right here ! "

On Jan 2, 10:30 am, "halee Rustumani" <hale...@hotmail.com> wrote:
> ImageAnalyst <imageanal...@mailinator.com> wrote in message <97d8aa14-b9bf-42ad-85be-16b4624d8...@a21g2000yqc.googlegroups.com>...
> > On Jan 2, 3:24 am, "halee Rustumani" <hale...@hotmail.com> wrote:
> > > Thanks alot Matt but I dont have time to search it i just need a quick solution
> > > [snip]
> > > thanks
> > ------------------------------------------------------------
> > But you'd have time to sit and wait an unknown length of time while
> > Matt or someone else does it for you????  What would you be doing
> > during that time?
>
> --------------------------------------------------------------
> Thanx a lot Image Analyst for your sweet words it seems that to some ppl knowledge means arrogance just a hint for ur future don’t ever judge ppl while you don’t know what there really going through you don’t even know me!!!!
> I won’t say more than god forgive you.

You need to ask Matt to forgive you for being such an ...

Greg

Dear ImageAnalyst!

>halee Rustumani wrote:
> I won’t say more than god forgive you.

I will say more than god forgive you: I forgive you :-)

I do have a chili pepper program. But due to the potential to use chili powder as a weapon, I'm not allowed to export it to countries, which have airports. I could offer a program for apples, but I'm still struggeling in a lawsuit with a famous american computer manufacturer. Then I've developped a program to detect growing cucumbers - it was bought by the agency for censorship of movies, which are harmful to minors. Finally I gave up the vegetable stuff.

Kind regards, Jan

"halee Rustumani" <halee89@hotmail.com> wrote in message <hhmvr3$87a$1@fred.mathworks.com>...

> ------------------------------------------------
> Thanks alot Matt but I dont have time to search it i just need a quick solution and as I heard it just something very minor that doesnt need alot of thinking I think its a built in function FFT just like you said but I need to know how it works
==================

The use of fft() *does* require a lot of thinking, as shown by the many questions and misconceptions about fft usage posted to this Newsgroup.

There is no way to get it right without reading "help fft" and that's only the beginning...