create a elip filter with a bandstop in matlab

main.m
Fs = 1000;          % sampling frequency
fstop1 = 40;        % first stopband frequency
fpass1 = 50;        % first passband frequency
fpass2 = 70;        % second passband frequency
fstop2 = 80;        % second stopband frequency
Astop1 = 60;        % first stopband attenuation
Apass = 1;          % passband ripple
Astop2 = 60;        % second stopband attenuation

% Compute the filter coefficients using the ellip function
[b, a] = ellip(6, Apass, Astop1, [fstop1 fpass1], 'bandpass', Fs);
[b2, a2] = ellip(6, Apass, Astop2, [fpass2 fstop2], 'bandpass', Fs);
[b_bandstop, a_bandstop] = conv(b, a2, 'full') + conv(b2, a, 'full');

% Generate the frequency response of the filter
fvtool(b_bandstop, a_bandstop);
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