id	summary	reporter	owner	description	type	status	priority	milestone	component	version	resolution	keywords	cc
4758	Issues with equation count in NF	Francesco Casella	Willi Braun	"Please check the [https://libraries.openmodelica.org/branches/newInst/Modelica_3.2.2/files/Modelica_3.2.2_Modelica.Blocks.Examples.FilterWithDifferentiation.err FilterWithDifferentiation] model with the NF. When checking the model, I get
{{{
Modelica.Blocks.Examples.FilterWithDifferentiation has
15 equation(s) and 15 variable(s).
}}}
and I can also count 15 equations if I flatten the model. However, when compiling the model the following error is obtained:
{{{
Error: Too many equations, over-determined system.
The model has 13 equation(s) and 11 variable(s).
Error: Internal error Transformation Module 
PFPlusExt index Reduction Method Pantelides failed!
}}}
As there are some equations involving complex functions, I suspect there is something wrong in how the DAE structure is built in that case."	defect	closed	high	2.0.0	Backend		fixed