MATLAB: Error using odearguments (line 93) PHASE_1 must return a column vector.

Question

Here is my call to ode45

[t,y] = ode45(@Phase_1, tspan, intial_conditions);

and here is the function i am referencing

function dydt = Phase_1(t, y)
dydt(1,1) = y(3);
dydt(1,2) = y(4);
dydt(1,3) = 2*t;
dydt(1,4) = 1.5*t;
dydt(1,5) = t^(1/9);
dydt(1,6) = t^(1/6);
end

when I call ode45 I get these error messages and I can't seem to figure out what I'm doing wrong. Any help would be much appreciated.

Error using odearguments (line 93)

PHASE_1 must return a column vector.

Error in ode45 (line 115)

odearguments(FcnHandlesUsed, solver_name, ode, tspan, y0, options, varargin);

Error in rocket_code (line 32)

[t,y] = ode45(@Phase_1, tspan, intial_conditions);

Answer 1

You have the indices reversed.

Try this:

function dydt = Phase_1(t, y)
dydt(1,1) = y(3);
dydt(2,1) = y(4);
dydt(3,1) = 2*t;
dydt(4,1) = 1.5*t;
dydt(5,1) = t^(1/9);
dydt(6,1) = t^(1/6);
end