error in code

I have this code:

      h=1; 
      a1=linspace(0,0,100); 
      a2=linspace(0.8,0.8,100); 
      a3=linspace(-0.8,-0.8,80); 
      a4=linspace(0,0,120); 
      kat=[a1 a2 a3 a4]; 

      x=[0.5 0.2 0.5]; 
      k=[linspace(0,0,400);linspace(0,0,400)]; 
      for i=1:1:400 
      k(i+1;:)=k(i;:)+h*F_tanker(x,kat(i))  ; 
      end

and when i try tu run it error occurs: Line: 11 Column: 6 Incomplete or misformed expression or statement.

Answer 1

[Jiro Doke]

Read this line carefully:

k(i+1;:)=k(i;:)+h*F_tanker(x,kat(i))  ;

You have a couple of extra ; in the line.

[Srinivas]

and then make sure you define

'F_tanker'

Answer 2

[John]

Can you be more specific which one of ; i shoul remove? I can't see one. F_tanker looks like this:

function [dx]=F_tanker(x,delta);

ell=350;      % Length of the ship (in meters)
u=5;        % Nominal speed (in meters/sec)

% The parameters for the tanker under "ballast" conditions 
% (a heavy ship) are:

% K_0=5.88;
% tau_10=-16.91;
% tau_20=0.45;
% tau_30=1.43;

% The parameters for the tanker under "full" conditions (a ship
% that weighs less than one under "ballast" conditions) are:

K_0=0.83;
tau_10=-2.88;
tau_20=0.38;
tau_30=1.07;

abar=1;             % Parameters for nonlinearity
bbar=1;

K=K_0*(u/ell);
tau_1=tau_10*(ell/u);
tau_2=tau_20*(ell/u);
tau_3=tau_30*(ell/u);

dx= [ x(2) ;
     x(3)+ (K*tau_3/(tau_1*tau_2))*delta;
    -((1/tau_1)+(1/tau_2))*(x(3)+ (K*tau_3/(tau_1*tau_2))*delta)-...
     (1/(tau_1*tau_2))*(abar*x(2)^3 + bbar*x(2)) + (K/(tau_1*tau_2))*delta];

Answer 3

[Srinivas]

this line

   k(i+1;:)=k(i;:)+h*F_tanker(x,kat(i))  ;

should be

   k(i+1,:)=k(i,:)+h*F_tanker(x,kat(i))  ;

go through some tutorials that will help http://www.mathworks.com/academia/student_center/tutorials/launchpad.html