ode15s error line 150

function [ydot, yinit, option] = Koo1( t , y , flag )

switch flag
case ''
    Cab=y(1);
    Caex=y(2);
    Cas=y(3);
    Cac=y(4);
    IP3=y(5);
    
        RT = 4.4*10^4;
        k1 = 6.0*10^-4;
        k2 = 1;
        k3 = 3.32;
        k4 = 2500;
        k5 = 5.0*10^-11;
        k6 = 0.05;
        k7 = 150;
        K1 = 0;
        K2 = 200;
        K3 = 150;
        K4 = 80;
        K5 = 321;
        Khi = 380;
        kCICR = 1;
        KCICR = 0;
        kCCE = 0;
        BT = 1.2*10^5;
        Ca0 = 100;
        Qshear = 3000;
        Vp = 815;
        Vex = 9165;
        Vhi = 2380;
        tau1 = 66;
        tau2 = 0.01;
        fracK = 7.07*10^6;
        
        v1 = k7 * Cab - k6 * Cac * (BT - Cab);
        v2 = kCCE * (((fracK * Ca0)/(K3 + Ca0)) - Cas) * (Caex - Cas);
        v3 = k1*(RT - (RT/2) * (exp(-t/tau1) + exp(-t/tau2) + ((exp(-t/tau1) - exp(-t/tau2)) * (tau1 + tau2) / (tau1 - tau2)))) * (exp(-t/tau1) -exp(-t/tau2)) * (Cac / (K1 + Cac));
        v4 = k2 * IP3;
        v5 = k3 * (kCICR * Cac / (KCICR + Cac)) * (IP3 / (K2 + IP3))^3 * Cas - k4 * (Cac/(K3 + Cac))^2 + k5 * Cas^2;
        v6 = Vex * Cac / (K5 + Cac);
        v7a = Vp * Cac^2 / ( K4^2 + Cac^2);       
        v7b= Vhi * Cac^4/( Khi^4 + Cac^4);
        v8 = Qshear;
        
        ydot = [- v1; 
                - v2 + v6 + v7a - v7b; 
                v2 - v5; 
                v1 + v5 + v8 - v6 -v7a -v7b;
                v3 -v4];
    case 'init'
                ydot = 0:1:900;
                yinit = [ 3870; 1.5*10^6; 2.83*10^6; 117.2; 0];
                option = odeset('RelTol',1.0e-7);
end

Errors:

>> [t,y] = ode15s( 'Koo1');
エラー: vertcat
連結する配列の次元が一致しません。

エラー: Koo1 (line 48)
        ydot = [- v1;

エラー: odearguments (line 90)
f0 = feval(ode,t0,y0,args{:});   % ODE15I sets args{1} to yp0.

エラー: ode15s (line 150)
    odearguments(FcnHandlesUsed, solver_name, ode, tspan, y0, options, varargin);

Answer 1

[Star Strider]

The problem is ‘ydot’. It must be a column vector, and the spaces are causing MATLAB to consider it a matrix. The easiest way to deal with that is simply to put parentheses around each element:

        ydot = [(- v1); 
                (- v2 + v6 + v7a - v7b); 
                (v2 - v5); 
                (v1 + v5 + v8 - v6 -v7a -v7b);
                (v3 -v4)];

That worked when I tested it.

Also, for that same reason, this is not going to work:

            ydot = 0:1:900;

You need to figure out some way of doing what you want with that in the context of the necessity that ‘ydot’ be a column vector.