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Bharat
Posts:
1
Registered:
11/20/12


Warning during integration: Matrix is close to singular or badly scaled
Posted:
Nov 20, 2012 3:53 AM


I have multiple doubts in this regard.
My system components are best represented as matrices (three coupled components in a physical unit which interact with different neighboring units [an array of units]).
But to pass it to an ODE solver I need vectorize the output of the odefun. This also requires me to convert y that is passed to odefun into a matrix. The vector size comes to ~1800. I was using ode23s with RelTol = 1e5 and AbsTol = 1e6
With a computer config of 8core 2GHz processor and 6GB RAM the equation is taking a long time to solve and the solver starts giving a warning "Matrix is close to singular or badly scaled". The solution is also not in the expected range.
I have the following doubts:
1. Which ode solver to use (i was thinking of using 113 because I dont expect the system to be very stiff along with setting NonNegative on)
2. Will quadv be a better option
3. Is there any other way to reduce computation time



