Hi i’m gonna open another discussion hoping more people will join it and someone will find the solution. I have a set of data which have been interpolated through Fourier Transform to build a function f(x)=A*cos(2*pi*F*x+P). All the coefficients have been succesfully calculated and the function fit perfectly the data. The problem is that when i try to plot the equation to further x value the function tends immediately to a stochastic behaviour (small amplitude-high frequency wave) which it doesn’t make any sense.
In other words after the interpolation period the function collapse immediately into its noise and strong amplitudes disappear.
Does anyone can solve this problem?
I attach the model.
Thanks for you all in advanceHi i’m gonna open another discussion hoping more people will join it and someone will find the solution. I have a set of data which have been interpolated through Fourier Transform to build a function f(x)=A*cos(2*pi*F*x+P). All the coefficients have been succesfully calculated and the function fit perfectly the data. The problem is that when i try to plot the equation to further x value the function tends immediately to a stochastic behaviour (small amplitude-high frequency wave) which it doesn’t make any sense.
In other words after the interpolation period the function collapse immediately into its noise and strong amplitudes disappear.
Does anyone can solve this problem?
I attach the model.
Thanks for you all in advance Hi i’m gonna open another discussion hoping more people will join it and someone will find the solution. I have a set of data which have been interpolated through Fourier Transform to build a function f(x)=A*cos(2*pi*F*x+P). All the coefficients have been succesfully calculated and the function fit perfectly the data. The problem is that when i try to plot the equation to further x value the function tends immediately to a stochastic behaviour (small amplitude-high frequency wave) which it doesn’t make any sense.
In other words after the interpolation period the function collapse immediately into its noise and strong amplitudes disappear.
Does anyone can solve this problem?
I attach the model.
Thanks for you all in advance fft, fourier, model, interpolation, amplitude, noise, function MATLAB Answers — New Questions

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