The problem statement i am trying to solve is a system of differential equations:
dx/dt = x - xy
dy/dt = -y + xy - yz
dz/dt = -z + .8yz
where x(0) = .5, y(0) = .5, and z(0) = 2
I have constructed a circuit involving integrator ckts to solve this problem. the circuit will run w/o .ic statements but the output isn't what is expected. i'm trying to resolve this issue by setting all nodes not connected to sources or involved in initial conditions to 0V using .ic statement. the problem is that, when i include these .ic statements i get a message "Singular matrix: check nodes 3:31 and 2:6 Iteration No. 2.
the mod file i'm using for the op-amp and the .cir files are in the zip file. thanks.
dx/dt = x - xy
dy/dt = -y + xy - yz
dz/dt = -z + .8yz
where x(0) = .5, y(0) = .5, and z(0) = 2
I have constructed a circuit involving integrator ckts to solve this problem. the circuit will run w/o .ic statements but the output isn't what is expected. i'm trying to resolve this issue by setting all nodes not connected to sources or involved in initial conditions to 0V using .ic statement. the problem is that, when i include these .ic statements i get a message "Singular matrix: check nodes 3:31 and 2:6 Iteration No. 2.
the mod file i'm using for the op-amp and the .cir files are in the zip file. thanks.
