I managed to solve the problem my rewriting the integrals to the proper syntax and evaluating them using the Toolbox. My substituting this result into the original equation I was able to obtain the solutions without unevaluated integrals.
Eliminate integral from symbolic differential system solution
1 view (last 30 days)
Show older comments
I use the Symbolic Toolbox to solve the following system:
sol_ct = dsolve(...
diff(cb) == -k4*cb + k3*cf, ...
diff(cf) == k4*cb - (k1/Vd + k3)*cf + k1*((A1*t-A2-A3)*exp(-L1*t) + A2*exp(-L2*t) + A3*exp(-L3*t)),...
cf(0) == 0, cb(0) == 0,'IgnoreAnalyticConstraints',true);
The odd thing is that the solutions of both cf and cb contain integrals like:
int(exp(-(x*(2*L1 + 2*L2 + 2*L3 - k2 - k3 - k4 + (k2^2 + 2*k2*k3 - 2*k2*k4 + k3^2 + 2*k3*k4 + k4^2)^(1/2)))/2)*(heaviside(tau - x) - 1)*(A2*exp(L1*tau + L2*x + L3*x) - A2*exp(L2*tau + L1*x + L3*x) + A3*exp(L1*tau + L2*x + L3*x) - A3*exp(L3*tau + L1*x + L2*x) + A1*tau*exp(L1*tau + L2*x + L3*x) - A1*x*exp(L1*tau + L2*x + L3*x)), x == 0..t)
Due to these integrals, it is not possible to export these solutions using MatlabFunction, which I require for further least squares fitting. Thus far I failed to either evaluate these integrals to find a way to export these solutions. Any help would be greatly appreciated!
0 Comments
Accepted Answer
More Answers (0)
See Also
Categories
Find more on Symbolic Math Toolbox in Help Center and File Exchange
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!