[hiep.nguyentrong]

Hello,
Im trying to implement freestreamVelocity boundary condition (OpenFOAM.com) to foam-extend-5.0 as dynamic lib but its show wrong types for operator=

freestreamVelocityFvPatchVectorField.C:66:17: error: no match for ‘operator=’ (operand types are ‘Foam::Field<Foam::Vector<double> >’ and ‘const Foam::zero’)
     refGrad() = Zero;

I checked both zero.H in openFOAM and foam-extend but can't find type of Zero
What should i do to fix this problem?

[hjasak]

refGrad() = vector::zero;