How can I change a single line color and style in a graph?

Hi! I have created a code that will generate 3 figures, with 8 lines in each figure.

I want to change the color and style of the lines individually, but can't seem to find a way that works. Any advice would be really helpful!

The code is shown here.

phistep = 0.0001;
phiarr = (0.25:phistep:5)';
numberofvalues = (5-0.25)/phistep+1;
d11 = 65493;
d12 = 1267;
d22 = 32243;
d66 = 1867;
marr = [1,2,3,4];
narr = [1,2];

for c = [0,1,2]
    linevalues = zeros(numberofvalues,length(marr)*length(narr));
    for m = marr
        for n = narr
            for i = 1:numberofvalues
                phi = phiarr(i);
                idx = (m-1)*(length(narr))+n;
                linevalues(i,idx) = ((pi^2)/(100^2))*(d11*(m/phi)^4 + 2*(d12+2*d66)*(m*n/phi)^2 + d22*n^4)/((m/phi)^2+c*n^2);
            end
        end
    end
    figure(c+1)
    phimat = repmat(phiarr,1,length(marr)*length(narr));
    [y_min, idx]=min(linevalues);
    x_min = phimat(idx);
    plot(phimat,linevalues,x_min,y_min,'rx');
    ylim([0 600]);
    xlabel('aspect ratio');
    ylabel('buckling load');
    grid on
    legend('m=1,n=1','m=1,n=2','m=2,n=1','m=2,n=2','m=3,n=1','m=3,n=2','m=4,n=1','m=4,n=2')
end

Answer 1

[Ameer Hamza]

Try this. It uses the color specified in colors variable

phistep = 0.0001;
phiarr = (0.25:phistep:5)';
numberofvalues = (5-0.25)/phistep+1;
d11 = 65493;
d12 = 1267;
d22 = 32243;
d66 = 1867;
marr = [1,2,3,4];
narr = [1,2];

colors = [0 0 0; %% <---- Define colors
          0 0 1;
          0 1 0;
          0 1 1;
          1 0 0;
          1 0 1;
          1 1 0;
          1 1 1]; % Give RGB value for eight lines. Each value can vary from 0 to 1

for c = [0,1,2]
    linevalues = zeros(numberofvalues,length(marr)*length(narr));
    for m = marr
        for n = narr
            for i = 1:numberofvalues
                phi = phiarr(i);
                idx = (m-1)*(length(narr))+n;
                linevalues(i,idx) = ((pi^2)/(100^2))*(d11*(m/phi)^4 + 2*(d12+2*d66)*(m*n/phi)^2 + d22*n^4)/((m/phi)^2+c*n^2);
            end
        end
    end
    figure(c+1)
    ax = axes(); 
    hold(ax); % we need to hold the axes
    phimat = repmat(phiarr,1,length(marr)*length(narr));
    [y_min, idx]=min(linevalues);
    x_min = phimat(idx);
    % Loop is needed to specify different colors
    for i=1:8
        plot(phimat(:,i),linevalues(:,i),'Color', colors(i,:));
    end
    plot(x_min,y_min,'rx');
    ylim([0 600]);
    xlabel('aspect ratio');
    ylabel('buckling load');
    grid on
    legend('m=1,n=1','m=1,n=2','m=2,n=1','m=2,n=2','m=3,n=1','m=3,n=2','m=4,n=1','m=4,n=2')
end

[Kurama Chan]

Hi Ameer! Thank you for the answer it works perfect!

Is there a way that I can change the line style as well for specific lines?

[Ameer Hamza]

After defining colors, just define a cell array of line style specifiers

lineStyles = {'-', '--', '.', ..} % make 8 elements

and then in plot statement

plot(phimat(:,i),linevalues(:,i),'Color', colors(i,:), 'LineStyle', lineStyles{i});