14 Replies Latest reply: Aug 20, 2002 12:00 AM by ptc-1368288

# Fourier transform of sin(Wt)

Hello

I would like to know how to find the fourier transform of the following using Mathcad:

x(t)=sin(2*pi*100*t)
Following Integral is not working
G(f)= intgral -infinity to + infinity (x(t)*exp(-j*2*PI*f*t)

Thanks

Leyo Joseph
• ###### Fourier transform of sin(Wt)
What version of Mathcad do you use?
Xavier
• ###### Fourier transform of sin(Wt)
There are many scaling factor for Fourier, but this does not affect the transform.

• ###### Fourier transform of sin(Wt)
Hello Xavier

I am not vey familiar with symbolic calculation...just catching up. Appreciate if you can get me Mathcad file with this implemented.

Regards

leyo Joseph
• ###### Fourier transform of sin(Wt)
Here is something in 2001i format.
Xavier
• ###### Fourier transform of sin(Wt)
Hello Xavier

I am unsing Mathcad 2000. Not able to open the Mathcad file in 2001 version you had posted. Appreciate if you can get me 2000 version.

Thanks

Leyo
• ###### Fourier transform of sin(Wt)
Here it is in 2000 format.
X
• ###### Fourier transform of sin(Wt)
Hello Xavier

Thanks... It works.

I have a function of time and want to plot the spectrum in frequency domain. Can I plot the symbolic calculated fourier function as function of (w)?.

Thanks

Leyo Joseph
• ###### Fourier transform of sin(Wt)
You can use the symbolic engine:

Xavier
• ###### Fourier transform of sin(Wt)
Review the functions "fft", "ifft", "FFT", and "iFFT".

Fred Kohlhepp
fkohlhepp@sikorsky.com
• ###### Fourier transform of sin(Wt)
That's where it gets ugly really fast! A distribution such as the Dirac distribution cannot be plotted as easily as a function. JMG showed examples in this thread where the Fourier transform has a usable close form.
The rest of the time you'll end up using a discrete Fourier transform calculation to display the function spectrum. Needless to say, one must be really careful about discrete sampling, windowing and aliasing effects...
If you have a specific function in mind we can certainly get you started.
Xavier
• ###### Fourier transform of sin(Wt)
Attached in 2000 is a tutorial about DFT and 'fft'. The overall presentation is not final but it contains lot of information and several examples.
_________DO NOT OPTIMIZE________
it will kill your box. It blocks at the definition of DFT and never stops and you can not stop calculating either !
It pushes the symbolic in corner.