MATLAB ode solver function is taking a very long time

I want to solve a differential equation . for this I am using ode23 solver. my differential equation function is given below.

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function dydt = pkodeB2(t,y)

global m b Ad f

uddot=-Ad*(2*pi*f)^2*cos(2*pi*f*t);

ydot=y(2); 

yddot=-(y(1).*b(1)+ y(2).*b(2)+y(1).^2.*y(2).*b(3)+ y(2).^3.*b(4)+y(1).^5.*b(5)+ y(1).^1.*y(2).^4.*b(6)+m*uddot)./(m);

dydt=[ydot;yddot];

told=t;

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y0=2/sqrt((-(b(3)/b(2))-3*(b(1)*b(4))/(m*b(2)))); 

ydot0=0; 

ystart=[y0 ydot0];

tspan=0:0.005:20; 

[t,y] =ode23(@pkodeB2,tspan,ystart);

where m= 70.9; Ad=0.03; f=1;and

b= [2868.808,  -696.923,   4800983.798,   90741.008,  -40781322891.737,    90262286.352]

when I run the code Matlab shows busy and it does not generate any value in one hour or more.

I want to know how I proceed to solve the above differential equation

Answer 1

[Steven Lord]

Try one of the stiffer solvers listed in the ODE documentation.