How can I fix "Not Enough Input Arguments" error in this Script?

Input:

t = 0:pi/50:10*pi;
x = (1/2)*(sin(2*t))+1;
y = (1/2)*(cos(2*t))+1;
z = 2*t;
plot3(x,y,z,t,'r','LineWidth',3)

Output:

Error using plot3
Not enough input arguments.

Error in testfunc (line 6)
plot3(x,y,z,t,'r','LineWidth',3)

[Sophia]

t = 0:pi/50:10*pi
x = (1/2)*(sin(2*t))+1;
y = (1/2)*(cos(2*t))+1;
z = 2*t;

figure(2);
plot3(x,y,z,'r','LineWidth',3)

[Stephen23]

@Tom Keaton: please show us the complete error message. This means all of the red text.

[OCDER]

Code works for me without error. Is there more to it?

[Tom Keaton]

@sophia Unfortunately, this did not work :/

[Tom Keaton]

@Stephen Cobeldick The post is updated so "Output" shows all the red text I see.

[Geoff Hayes]

Tom - which version of MATLAB are you using? If you look at that the documentation for that version (call doc plot3 from the command line) does your code satisfy the documentation description (in particular the signature for plot3)?

Note that the online documentation is for the most recent version of MATLAB (you can find archived versions though) so it may conflict with whatever version you have.

[OCDER]

@sophia's code worked for me.

plot3(x,y,z,t,'r','LineWidth',3) 
          ^ ^  your code has an extra t or z input.

Maybe Mathworks could change the error message to something like this:

Error using plot3
Incorrect number of input arguments.

So what do you expect a 3D plot will do with 4 dimensions of data - (x, y, z, t)? Maybe you need another plot, or a video perhaps?

[Tom Keaton]

@OCDER That was the issue. I got rid of the extra variable and it works now. I thought I was supposed to define the independent variable per MatLab formatting but I guess that was not the case. Thanks.

[Greg]

"Not enough input arguments" is the correct error message because plot3 allows indefinite triplets of x,y,z inputs. Therefore, it thinks "t" is the first dimension of the second triplet, meaning 2 more inputs must follow.

[OCDER]

@Tom, glad it worked!

@Greg, I guess that explains why Mathworks put that error message. But, "Incorrect number of input arguments" INCLUDES "Not enough input arguments" AND "Too many input arguments". In this case, there was too many input arguments, which was the opposite of "not enough input arguments" - this could make debugging a little confusing.

[Greg]

Maybe you're right. Personally, MATLAB's documentation makes 100% perfect sense to me, so I just look up the calling syntax and fix it. It's probably the single most prominent reason I'm proficient with MATLAB - my brain just works exactly the way the documentation is laid out. Others might not be so lucky.

Answer 1

[KSSV]

t = 0:pi/50:10*pi;
x = (1/2)*(sin(2*t))+1;
y = (1/2)*(cos(2*t))+1;
z = 2*t;
plot3(x,y,z,'r','LineWidth',3)

You need not plot t here. plot3 takes only three inputs of data i.e (x,y,z).