ERROR: Material property is not defined on block 0

[LiuPengPeter]

Hello guys,
*** ERROR ***
Material property 'v_Coefficient', requested by 'StudyCoefficientGradientV' is not defined on block 0
code.zip

I checked my exercise codes for many times and still couldn't solve the problem... Could anyone help?

[WilkAndy]

This is probably not due to your C code. It is probably due to your input file. Your input file needs a Material block that will produce a MaterialProperty called "v_Coefficient", since your "StudyCoefficientGradientV" Material needs that MaterialProperty.

[LiuPengPeter]

My .i file is also in the zip.

`[Kernels]
[./DiffusionU]
type = Diffusion
variable = u
[../]
[./StudyCoefficientGradientV]
type = StudyCoefficientGradientV
variable = u
D = v_Coefficient
[../]

`[Materials]
[./StudyMaterialCoefficientGradientV]
type = StudyMaterialCoefficientGradientV
D = v_Coefficient
v = v
[../]

Is there something wrong?

[cpgr]

The problem is in your StudyMaterialCoefficientGradientV material. Take a look at this bit:

   _v_coefficient_name(getParam<MaterialPropertyName>("D")),
   _v_coefficient(declareProperty<RealGradient>("_v_coefficient_name"))

You are declaring a property called _v_coefficient_name (that actual string), not whatever you enter in the parameter D in your input file. Simply remove the "" in the second line and it should work as you are now declaring a property with the name given in the input file.

[LiuPengPeter]

Thanks a lot!

[WilkAndy]

@cpgr saves the day again!