plot signal - adjust axis

i have signal between |f|<100 Hz

and i need to present it the range of |f|<125 Hz

MY PROBLEM is that i want to have a continuity between the output signal to the outrange 100<f<125 to be a solid line

in this range the output signal doesnt exist so it just cutted with no bound to x axis

IN SIMPLE WORDS

to add contiuetinity (yellow line to the x axis)

thanks for help!

Answer 1

[Chunru]

% Test data
f = (-100:1:100);
p = randn(size(f)); p = p-min(p)+1;

% extropolate data
fe = [-125 f 125];

pe = interp1(fe, [0 p 0],  fe, 'linear', 'extrap');
plot (fe, pe)
axis tight
grid on

[Ido]

thanks for answering

but my signal is maded from few rand cos(wt) so the boundaries should be more smoothly like 1/1-x

i used meshgrid so it didnt considered the area bettween 100<|f|<125

theres another way to solve it ?

[Chunru]

Can you share your data and code?