t = -2:2;

color = ['r', 'g', 'b', 'k', 'c' ];

for N = 1:5

    x = t.^2;
    y = t.^3;
    [th,r]=cart2pol(x,y);

    switch N
        case 1
            subplot(3,2,N)
            polar(th, r, color(N))
            hold on
        case 2
            subplot(3,2,N)
            polar(th, r, color(N))
            hold on
        case 3
            subplot(3,2,N)
            polar(th, r, color(N))
            hold on
        case 4
            subplot(3,2,N)
            polar(th, r, color(N))
            hold on
        case 5
            subplot(3,2,N)
            polar(th, r, color(N))


            hold on
        otherwise
            disp('error')
    end

    t = t + 1;

end