Add 2d plots along a 3d helix

Hello.

I have a simple helix that I've plotted by using the following code:

r=93.36;
theta=0:pi/50:10*pi;

%Trajectory in x-direction
x=-r.*cos(theta);
%Trajectory in y-direction
y=r.*sin(theta);
%Trajectory in z-direction
z=theta;

figure(1);
plot3(x,y,z);
xlabel('x');
ylabel('y');
zlabel('z');
grid on

My goal now is to also plot on the same graph the x and y components of the helix given from the equations above.

Thank you.

Answer 1

[Subhadeep Koley]

Use this

close all; clc;
r=93.36;
theta=0:pi/50:10*pi;
%Trajectory in x-direction
x=-r.*cos(theta);
%Trajectory in y-direction
y=r.*sin(theta);
%Trajectory in z-direction
z=theta;
figure(1);
plot3(x,y,z);
xlabel('x');
ylabel('y');
zlabel('z');
grid on
hold on;
plot(x, y, 'r', 'LineWidth', 3);

[Vivi]

Thank you but i want two plots where the first one is a plot of x against theta and then seconf a plot of y against theta as well.

[Subhadeep Koley]

@ Vivi I am not sure but it seems you want something like below

close all; clc;
r = 93.36;
theta = 0: pi/50: 10*pi;
% Trajectory in x-direction
x = -r .* cos(theta);
% Trajectory in y-direction
y = r .* sin(theta);
% Trajectory in z-direction
z = theta;
figure;
plot3(x, y, z, 'b');
xlabel('x');
ylabel('y');
zlabel('z');
grid on; box on;
hold on;
% Plot x against theta
axis([-101 101 -101 101 -1 36]);    
SX = size(x);
Y3 = 101 * ones(SX);
plot3(x, Y3, z, 'r', 'LineWidth', 1.5);
% Plot y against theta
SY = size(y);
X3 = 101 * ones(SY);
plot3(X3, y, z, 'g', 'LineWidth', 1.5);
hold off;

[Vivi]

That's the one. Thank you!

[connor brisebois]

could you explain te use of colon operators in the definition of theta?

[Subhadeep Koley]

Refer to the below link for a detailed explanation.

https://www.mathworks.com/help/matlab/ref/colon.html#bvhfyce