id	summary	reporter	owner	description	type	status	priority	milestone	component	version	resolution	keywords	cc
5160	Derivative information lost by the NF	Francesco Casella	Per Östlund	"Please check [https://libraries.openmodelica.org/branches/newInst/Modelica_trunk/files/Modelica_trunk_Modelica.Media.Examples.TestOnly.IdealGasN2Mix.err Modelica.Media.Examples.TestOnly.IdealGasN2Mix]. The NF fails with
{{{
[OMCompiler/Compiler/BackEnd/Differentiate.mo:402:3-402:155:writable] 
Error: Derivative of expression ""medium.h = 
Modelica.Media.Examples.TestOnly.IdealGasN2Mix.Medium.h_TX(medium.T, {1.0}, true, Modelica.Media.Interfaces.Choices.ReferenceEnthalpy.ZeroAt0K, 0.0)""
w.r.t. ""time"" is non-existent.
[Modelica trunk/Media/IdealGases/Common/package.mo:649:5-649:19:writable]
Error: Internal error 
Differentiate.differentiateEquationTime failed for
medium.h = Modelica.Media.Examples.TestOnly.IdealGasN2Mix.Medium.h_TX(medium.T, {1.0}, true, Modelica.Media.Interfaces.Choices.ReferenceEnthalpy.ZeroAt0K, 0.0)
}}}
apparently, some information is lost by the NF that prevents to correctly differentiate the equation - maybe the derivative annotation?"	defect	closed	high	2.0.0	New Instantiation		fixed