Error using ode45 (line 87) Not enough input arguments. See ODE45.

function molarflow

%[V,F] = solver(ode45,'q2', [0,1], [0.15;0.85;0;0;0]);

Fa = f(1);
Fo = f(2);
Fn = f(3);
Fw = f(4);
x = f(5);

k = 1;
Ft = Fa+Fo+Fn+Fw;
Fa0 = 0.15;
Fo0 = 0.85;
vf0 = 5;

ct0 = Fo0/vf0 +Fa0/vf0;
ca = ct0*Fa0/Ft;
co = ct0*Fo0/Ft;

ra = -k*ca^2*co;

dFadV = ra*4;
dF0dV = ra*5;
dFndV = -ra*4;
dFwdV = -ra*6;
dxdV = -ra/Fo0;

molarflow = [dFadV; dF0dV; dFndV; dFwdV; dxdV];

when i put [V,F] = solver(ode45,'q2', [0,1], [0.15;0.85;0;0;0]); to mathlab it comes with error Error using ode45 (line 87) Not enough input arguments. See ODE45. please help

[Geoff Hayes]

aysan - why not just remove the solver function and call ode45 directly as

 [V,F] = ode45('q2',[0,1], [0.15;0.85;0;0;0]);

Preasumably q2 is a function that you have defined somewhere within the MATLAB search path.

(To be honest, I don't know what the solver call does only that it doesn't seem to pass the inputs that you have provided correctly to ode45.)

Answer 1

[Jan]

In this line

   [V,F] = solver(ode45, 'q2', [0,1], [0.15;0.85;0;0;0])

the function ode45 is called without any inputs. It is equivalent to:

   [V,F] = solver(ode45(), 'q2', [0,1], [0.15;0.85;0;0;0])

I don't know, what solver is, but perhaps you want:

   [V,F] = solver(@ode45, 'q2', [0,1], [0.15;0.85;0;0;0])

In the following line you access "f(1)", but there is no variable "f".