How to zero the region of the FFT output?

How do I zero the rigion of the FFT output before plotting? The zero frequency region will be at the left hand side of the output plot:

I would like to zero the high value peaks at the extreme ends of th eplot and replot to bring up the signals in between.

How would I zero this region?

This is parts of the code of the algorithm:

t = sym(1):1:sym(P); % Signal duration/length

fncT = (T.^t) - floor(T.^t/M)*M; % Alternative version to mod(a,b)

% Fast fourier Transforms 1-D

A = fftshift(double(fncT)); % Rearranges 'fncT' by shifting the zero-frequency component to the centre of the array

A = fft(A); % Computes duscrete fourier transform of A using fft algorithm

A_mag = abs(A.*A);

Answer 1

[Star Strider]

If you want to set the 0 frequency d-c (constant offset) component of the fft result to 0, subtract the mean of the signal from the signal before calculating the fft:

FTsignal = fft(signal - mean(signal))/numel(signal);

This removes the d-c offset and normalises by the length of the signal.