Van Der Pol. Error. Not enough input arguments.

 Hello.

I have just copy the program Van Der Pol resolution from mathworks.

This program:

function dy = vdp1000(t,y)
dy = zeros(2,1);    % a column vector
dy(1) = y(2); 
dy(2) = 1000*(1 - y(1)^2)*y(2) - y(1);

[T,Y] = ode15s(@vdp1000,[0 3000],[2 0]);
plot(T,Y(:,1),'-o')

when I run the program, appear the next error:

vdp1000
Error using vdp1000 (line 3)
Not enough input arguments.
The line 3 is: dy(1) = y(2);

what do I make wrong?

I would be very grateful to someone who helps me.

Best regards,

MJ

Answer 1

[Walter Roberson]

You need to split that code into two parts.

[T,Y] = ode15s(@vdp1000,[0 3000],[2 0]);
plot(T,Y(:,1),'-o')

should be in one file, and

function dy = vdp1000(t,y)
dy = zeros(2,1);    % a column vector
dy(1) = y(2); 
dy(2) = 1000*(1 - y(1)^2)*y(2) - y(1);

should be in vdp1000.

You would invoke the other file, not the vdp1000 file.