How can I run multiple bisect programs in one file?

I have created bisection function files (five) and would like to combine them into one file to run. Below are the first 3.

File 1:

function f = enth2(T) 
% For phi=0.2
HR=-249400; % Total enthalpy of reactants.
hO2  = 31.999*(1.507.*(T-298) - 33.54.*(sqrt(T)-sqrt(298)) + 111.1.*log(T/298));
hN2  = 28.013*(1.450.*(T-298) - 287.9.*log(T/298) + (5.35e4).*((1/298)-(1./T)));
hCO2 = 44.01*(1.540.*(T-298) - 245.1.*log(T/298) + (4.13e4).*((1/298)-(1./T)));
hH2O = 18.015*(4.613.*(T-298) - 206.6.*(sqrt(T)-sqrt(298)) + 967.5.*log(T/298));
HP = -6595306+11*(hH2O)+10*(hCO2)+62*(hO2)+291.4*(hN2);
f=HR-HP;
end

File 2:

function f = enth3(T) 
% For phi=0.4.
HR=-249400; % Total enthalpy of reactants.
hO2  = 31.999*(1.507.*(T-298) - 33.54.*(sqrt(T)-sqrt(298)) + 111.1.*log(T/298));
hN2  = 28.013*(1.450.*(T-298) - 287.9.*log(T/298) + (5.35e4).*((1/298)-(1./T)));
hCO2 = 44.01*(1.540.*(T-298) - 245.1.*log(T/298) + (4.13e4).*((1/298)-(1./T)));
hH2O = 18.015*(4.613.*(T-298) - 206.6.*(sqrt(T)-sqrt(298)) + 967.5.*log(T/298));
HP = -6595306+11.*(hH2O)+10.*(hCO2)+23.25.*(hO2)+145.7.*(hN2);
f = HR-HP;
end

File 3:

 function f = enth4(T) 
% For phi=0.6
HR=-249400; % Total enthalpy of reactants.
hO2  = 31.999*(1.507.*(T-298) - 33.54.*(sqrt(T)-sqrt(298)) + 111.1.*log(T/298));
hN2  = 28.013*(1.450.*(T-298) - 287.9.*log(T/298) + (5.35e4).*((1/298)-(1./T)));
hCO2 = 44.01*(1.540.*(T-298) - 245.1.*log(T/298) + (4.13e4).*((1/298)-(1./T)));
hH2O = 18.015*(4.613.*(T-298) - 206.6.*(sqrt(T)-sqrt(298)) + 967.5.*log(T/298));
f=HR-(-6595306+11.*(hH2O)+10.*(hCO2)+10.33.*(hO2)+97.13.*(hN2));
end

[Jan]

What do you want to achieve by this combination? We cannot guess this important detail.