Why doesn't my code for Euler's method work?

function [T,N] = expgrowthEULER(N0,tmax,dt,r);
T=[0:dt:tmax]
N=zeros(length(T),1)
N(1)=N0
for i=2:length(T)
    N(i)=N(i-1)+r*N(i-1)*dt
end 
end 

N0=1
r=0.1
tmax=10
dt=0.1
[T,N]=expgrowthEULER(N0,tmax,dt,r)
plot(T,N)

It says I have an undefined variable 't'.

Answer 1

[madhan ravi]

correct usage is as shown below:

N0=1;
r=0.1;
tmax=10;
dt=0.1;
[T,N]=expgrowthEULER(N0,tmax,dt,r) ;   %function call
plot(T,N)


function [T,N] = expgrowthEULER(N0,tmax,dt,r)    % function definition
T=[0:dt:tmax];
N=zeros(length(T),1);
N(1)=N0;
for i=2:length(T)
    N(i)=N(i-1)+r*N(i-1)*dt;
end 
end