Having error 'Invalid array indexing'. Please help me to solve this issue

% Solve using Euler method

for i = 1:num_steps

v1_euler(i+1) = v1_euler(i) + dt * f(t(i), v1_euler(i), v2_euler(i))(1);

v2_euler(i+1) = v2_euler(i) + dt * f(t(i), v1_euler(i), v2_euler(i))(2);

Answer 1

[Image Analyst]

What is f? If f is a function you can't do this:

f(t(i), v1_euler(i), v2_euler(i))(1)

You'd need to get the results (returned vector) from f, then do f(1)

for example

result = f(t(i), v1_euler(i), v2_euler(i)); % Get result vector out of "f" function.
v1_euler(i+1) = v1_euler(i) + dt *result(1);