## Circuits and Dynamics Solver - Matrix Definition - C.1.perm usage?

Numerical methods and mathematical models of Elmer
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### Circuits and Dynamics Solver - Matrix Definition - C.1.perm usage?

Hello all,

I have a question regarding the Matrix definition (Circuit definition) for the Circuits and Dynamics Solver and the Coil Current Solver.
In some of the examples in the coil-circuits.definitions files (see example below) the Matrix C.1.perm=zeros(4) is defined, followed by a redefinition (permutation?) of the values. In other examples only Matrix C.1.perm=zeros(4) is defined.
What is the impact on the circuit definition of this redefinition of the C.1.perm Values?
What is the difference for the definitions in the ElmerSover xxx.sif File if C.1.perm is redefined or if the original definition with Matrix C.1.perm=zeros(4) is used?

Maybe someone can give me a hint? I can't find any information regrading the usage and the impact of the C.1.perm definition.

coil-circuits.definitions
Example of CircuitsTransientStrandedFullCoil

\$ Circuits = 1
! ------------------------ Circuit 1 ------------------------
! Define variable count and initialize circuit matrices.
\$ C.1.perm = zeros(4)
\$ C.1.perm(3) = 0
\$ C.1.perm(2) = 1
\$ C.1.perm(0) = 2
\$ C.1.perm(1) = 3

\$ C.1.variables = 4
\$ C.1.A = zeros(4,4)
\$ C.1.B = zeros(4,4)

! Define variables.
\$ C.1.name.1 = "i_component(1)"
\$ C.1.name.2 = "v_component(1)"
\$ C.1.name.3 = "i_S1"
\$ C.1.name.4 = "v_S1"

! Define sources:
!------------------
\$ C.1.B(0,2) = 1
\$ C.1.source.3 = "S1"

! Define network cycles:
!-------------------------
!Voltage relations.
\$ C.1.B(2,3) = 1
\$ C.1.B(2,1) = 1
!Current relations.
\$ C.1.B(3,2) = 1
\$ C.1.B(3,0) = -1