What does STEM plot in MATLAB indicates? what does it indicates if stem( FFT(x(t))) of a signal x(t) is drawn ? What is its importance?

What does STEM plot in MATLAB indicates? what does it indicates if stem( FFT(x(t))) of a signal x(t) is drawn ? What is its importance?

[dpb]

It's just a plot drawn as vertical lines from the axis instead of simply connecting the points.

A plot of the fft of a signal by itself is probably not of much significance at all; it willl simply be the real porition of the complex FFT of the signal as the graphics routines ignore the complex portions.

You'd have to have the context to understand what importance there might be; stem itself is definitely immaterial in that regards.

[dpb]

There's the special case that iff the input signal is real and symmetric, the FFT output is real. In that case, then the above caveat regarding magnitude would disappear. However, unless the input has been contrived to be such or for some specific reason is such, then it would seem the plotting of the fft() result itself would likely not be of much real use.

Again, like in real estate, "location, location, location!". Need to know the context.