Hi there,
I am struggling with obtaining the Hessian of my function. In the first case it works fine but in the second case I can not get it (still symbolic variables X are presented in H). So my question is why this happen? This is small portion of the code where I want to find hessian of my Rtot function with X being x1,x2,x3,x4.
Rtot= -sum(Rsub(:,i));
H=hessian(Rtot,X);
H1 = 0.5.*double(H);
with Rtot:
(6234858085755363*x1*((17865509505801117*x1)/14411518807585587200000 + (17865509505801117*x3)/14411518807585587200000 - 16863388614392257743519/1441151880758558720000))/140737488355328000 + (6069173180546921*x2*((17865509505801117*x1)/7205759403792793600000 + (17865509505801117*x2)/14411518807585587200000 + (17865509505801117*x3)/7205759403792793600000 + (17865509505801117*x4)/14411518807585587200000 - 16867211833426499182557/1441151880758558720000))/140737488355328000
and H1:
1.0e-07 *
0.5492 0.5346 0.2746 0
0.5346 0.5346 0.5346 0.2673
0.2746 0.5346 0 0
0 0.2673 0 0
This is fine. But then when I want to find hessian of different data set i get this. Rtot:
- (2587079436111693477*x2*(665101922855875194446501149/3153075739026468800000 - (4398046511104*x2)/5912017010674629 - (4398046511104*x3)/5912017010674629 - (4398046511104*x4)/5912017010674629 - (4398046511104*x1)/5912017010674629)^(1/3))/28147497671065600000000 - (4554081285294461427*x1*(1299027180826527113674752/6158351052786071875 - (4398046511104*x3)/5912017010674629 - (4398046511104*x1)/5912017010674629)^(1/3))/56294995342131200000000
and H still have symbolic variables inside which does not allow me to calculate H1. Difference is in Rtot but I still can not find out why it does not work.
Thank you a lot!!!
