What is problem to make space curve [2*cos(t),2*sin(t),5]?

>> t = 0:pi/10:pi;

>> plot3(2*cos(t),2*sin(t),5)

Error occurred while using: plot3

Vectors should be the same length.

What should I do?

Answer 1

[Steven Lord]

You want to draw this curve in the section of 3-d space in the plane z = 5? You need to specify one z coordinate for each coordinate in x and y. plot3 doesn't do scalar expansion like many other functions do.

>> t = 0:pi/10:pi;
>> plot3(2*cos(t),2*sin(t),repmat(5, size(t)))

[seongjin park]

Thank you!

Answer 2

[Image Analyst]

Not sure what the 5 is for, but maybe you mean this, using plot3() to plot a 3-D curve:

t = 0 : pi/10 : pi;
plot3(t, 2*cos(t),2*sin(t), 'b.-', 'LineWidth', 2, 'MarkerSize', 20)
grid on;
xlabel('t', 'FontSize', 15);
ylabel('y', 'FontSize', 15);
zlabel('z', 'FontSize', 15);

or maybe you mean this, using plot() to plot a 2-D curve:

t = 0 : pi/10 : pi;
plot(2*cos(t),2*sin(t), 'b.-', 'LineWidth', 2, 'MarkerSize', 20)
grid on;
xlabel('t', 'FontSize', 15);
ylabel('y', 'FontSize', 15);