Negative value of signals

1. What does a negative value in FFT mean?
2. Can FFT have negative values?
3. What is positive signal?
4. What do you think is the importance of knowing the positive and negative signals in business?

What does a negative value in FFT mean?

Negative values in the real component of the result of a complex FFT correspond to a negative correlation with a cosine waveform (same as a 180 degree phase shift). If you want to check the energy at each frequency, graph the magnitude (sqrt(rere+imim)) of each complex FFT result bin.

Can FFT have negative values?

FFT gave a result in complex coordinates. Absolute value of all data points should be taken . Power values are absolute values of complex numbers derived from FFT. They can not be negative unless they are contrasted to baseline or other conditions.

What is positive signal?

A positive signal arriving at a neuron increases its total signal count or potential by one; a negative signal reduces it by one if the potential is positive, and has no effect if it is zero.

What do you think is the importance of knowing the positive and negative signals in business?

Understanding these negative customers and the heterogeneity among them can greatly improve your business. If you don't get a positive result from an experiment, a new marketing campaign or a different sales strategy, don't think you got nothing. The “nothing”, negative signal, is a signal.