How to make real and imaginary plot of the graph same color

In my code I have a for loop and with every iteration i tell matlab to draw real part of the curve as a solid line and imaginary part of the curve as a dashed line. What I would like to have is for each iteration the real and imaginary part of the same curve to have the same color, could anyone help?

clear all

%%
v=0:1e+9:1e+12;  %Frequency   (Hertz)

t0=0;            %Minimum Temperature (Celsius)
tstep=20;        %Temperature Step
tmax=100;        %Maximum Temperature
%%

for t=t0:tstep:tmax
    t=t';
    tc=133.1383;
    a=[79.23882 3.815866 1.634967];
    b=[0.004300598 0.01117295 0.006841548];
    c=[1.382264e-13 3.510354e-16 6.30035e-15];
    d=[652.7648 1249.533 405.5169];
    delta=a.*exp(-b.*t);
    tau=c.*exp(d./(t+tc));
    es=87.9144 - 0.404399.*t + 9.58726*10^(-4).*t.^2 -1.32802*10^(-6).*t.^3;
    
    p0=0.8379692;
    p1=-0.006118594;
    p2=-0.000012936798;
    p3=4235901000000;
    p4=-14260880000;
    p5=273815700;
    p6=-1246943;
    p7=9.618642e-14;
    p8=1.795786e-16;
    p9=-9.310017e-18;
    p10=1.655473e-19;
    p11=0.6165532;
    p12=0.007238532;
    p13=-0.00009523366;
    p14=15983170000000;
    p15=-74413570000;
    p16=497448000;
    p17=2.882476e-14;
    p18=-3.142118e-16;
    p19=3.528051e-18;
    
    delta4=p0+p1.*t+p2.*t.^2;
    delta5=p11+p12.*t+p13.*t.^2;
    tau4=p7+p8.*t+p9.*t.^2+p10.*t.^3;
    tau5=p17+p18.*t+p19.*t.^2;
    func4=p3+p4.*t+p5.*t.^2+p6.*t.^3;
    func5=p14+p15.*t+p16.*t.^2;
    
    e_real=es-(2*pi.*v).^2.*(...
        tau(1).^2*delta(1)./(1+(2*pi.*v.*tau(1)).^2)+...
        tau(2).^2*delta(2)./(1+(2*pi.*v.*tau(2)).^2)+...
        tau(3).^2*delta(3)./(1+(2*pi.*v.*tau(3)).^2))...
        -(2*pi.*tau4).^2.*0.5.*delta4.*(...
        v.*(func4+v)./(1+(2*pi.*tau4.*(func4+v)).^2)-...
        v.*(func4-v)./(1+(2*pi.*tau4.*(func4-v)).^2))...
        -(2*pi.*tau5).^2.*0.5.*delta5.*(...
        v.*(func5+v)./(1+(2*pi.*tau5.*(func5+v)).^2)-...
        v.*(func5-v)./(1+(2*pi.*tau5.*(func5-v)).^2));
    
    e_imag=2.*pi.*v.*(...
        tau(1).*delta(1)./(1+(2.*pi.*v.*tau(1)).^2)+...
        tau(2).*delta(2)./(1+(2*pi.*v.*tau(2)).^2)+...
        tau(3).*delta(3)./(1+(2*pi.*v.*tau(3)).^2))+...
        pi.*v.*tau4.*delta4.*(...
        1./(1+(2*pi.*tau4.*(func4+v)).^2)+...
        1./(1+(2*pi.*tau4.*(func4-v)).^2))+...
        pi.*v.*tau5.*delta5.*(...
        1./(1+(2*pi.*tau5.*(func5+v)).^2)+...
        1./(1+(2*pi.*tau5.*(func5-v)).^2));
    
    e=e_real+1j.*e_imag;
    
    semilogx(imag(e),'--')
    set(gca,'FontSize',20);
    set(gca,'Color','k');
    title('Relative Permittivity of Water vs Frequency & Water Temperature', 'Fontsize', 40);
    xlabel('Frequency (Hz)','Fontsize', 40) ;
    ylabel('Relative Permittivity', 'Fontsize', 40) ;
    
    hold on
    semilogx(real(e))
end

Answer 1

[Giuseppe Inghilterra]

Hi,

a fast and easy solution could be generate a triplette of RGB values randomly at each iteration and you use it as color for both plots, as you can see in the following code:

    RGB = rand(3,1);
    semilogx(imag(e),'--','Color',RGB)
    set(gca,'FontSize',20);
    set(gca,'Color','k');
    title('Relative Permittivity of Water vs Frequency & Water Temperature', 'Fontsize', 40);
    xlabel('Frequency (Hz)','Fontsize', 40) ;
    ylabel('Relative Permittivity', 'Fontsize', 40) ;
    
    hold on
    semilogx(real(e),'Color',RGB)

I have defined RGB vector that I use as color property for both plots. In this way both plots have the same color.

An alternative you could define a matrix of RGB values in order to control which color you want at each iteration for both plots.

Hope this helps.

[Sebastian Kudera]

This works great, thanks for the help!