Time for action - plotting parametric curves

1. 1. First, we need to instantiate the variable x, for example:

octave:118> x = linspace(0, 10*pi)';

1. 2. Then, we calculate the range of f:

octave:119> f = [cos(x), sin(x), exp(-0.5*x)];

1. 3. Just check that we got the right size:

octave:120> size(f)
ans =
100 3

1. 4. We can now plot the curve using plot3:

octave:121> plot3(f(:,1), f(:,2), f(:,3), "linewidth", 4)

1. 5. To set the right properties, we can use:

octave:122> set(gca, "linewidth", 2, "fontsize", 20);
octave:123> set(gca, "xlabel", text("string", "x","fontsize", 30);
octave:124> set(gca, "ylabel", text("string", "y","fontsize", 30);
octave:125> set(gca, "zlabel", text("string", "z","fontsize", 30);
octave:126> set(gca, "zlim", [0 1.2])
octave:127> text(0.9, -0.25, 0.9, "t=0", "fontsize", 30)
octave:128> view(20,30)

• Phew! The final figure is shown below:

What just happened?

In Command 119, we calculated the range of the interval—notice the transpose operator in Command...