Program for generating a FFT in Matlab

[issofa]

Hello there.

Please guys can someone help me with a small program in matlab to generate a frequency domain signal like the one in the attachment? I mean having some line signal.

Many Thanks.

 

[JoannesPaulus]

Generating a fft

After calculating the fft, you can plot it using "stem".

 

[issofa]

Re: Generating a fft

Hi,

Many thanks Paulus I have used the stemm command as u said but I have this circle at the end of the line is there anyway to remove them so that I can only have a straight line?

u can have a look on my attachment

Many thanks

 

[JoannesPaulus]

Generating a fft

you can use "stem(x,y,'.')", instead of the circle you will get a little dot...

 

[issofa]

Re: Generating a fft

Thanks again.

I have been able to get the dot with the line u have suggested. Another problem I'm facing is to get the amplitude in dB I have used 'semilogy' but it doesn't seem to be working is there any other option?

Many thanks.

 

[JoannesPaulus]

Generating a fft

What about 20*log10? ;-)