finished clean

src/spicelib/devices/hicum2/hicumL2.cpp

@@ -2466,6 +2466,8 @@ HICUMload(GENmodel *inModel, CKTcircuit *ckt)
                 }
             }
 
+            // Write DC Currents and thei derivatives on the correct variables of the HiCUM equivalent circuit
+
             *(ckt->CKTstate0 + here->HICUMvbiei)       = Vbiei;
             *(ckt->CKTstate0 + here->HICUMvbici)       = Vbici;
             *(ckt->CKTstate0 + here->HICUMvbpei)       = Vbpei;
@@ -2520,6 +2522,7 @@ load:
             /*
              *  load current excitation vector and matrix
              */
+            // Markus: As far as I understand this: Derivative of Kirchhoff Current law for every node
 /*
 c           Branch: be, Stamp element: Cbepar1
 */

src/spicelib/devices/hicum2/overview_files.md

@@ -62,3 +62,7 @@ See test case in DMT where this is compared against ADS.
 - re
 - Ibiei
 - Ibici
+
+# useful stuff
+- non-ancient explanation how equation system of spice looks:
+https://spicesharp.github.io/SpiceSharp/articles/custom_components/modified_nodal_analysis.html#nonlinear-components