I need help with create a function

Well I have problems to create my function, that resolves a 2 simultaneous equations. ODE by Euler's Step. here is my script:

function y = funcion(u,v)
y(1)= u*(v-2)
y(2)= v*(1-u)
end

function y1= metodoeuler(h,u0,v0)
y1 = u0 + h*funcion(u0,v0)

%initial time
v0 =0;
%final time
ufinal = 10;
%number of steps
nsteps = 80;
y =[2;2];
%step size
h= (ufinal - v0)/ nsteps;
%set the variable t.
v = v0;
%go through the steps
for j=1 : nsteps
  u = metodoeuler(h,u,v);
  v = v + h;
  %saved output for u(t) only, i.e. the first component of y.
  tout(j) = t;
  d(j) = y(1);
end
%draw a figure for the solution u
plot(tout,u,'-')

The warning its that u its my incognite ... i cant undestand

[Walter Roberson]

Please show us the warning message or error message.