Hi Zhicheng, We have recently been trying to homogenise and update the field convert utility. Could I ask if you have tried it on the branch feature/FieldConvertCleanUp. Hopefully it will be working in this branch. We hope to get this branch into Master soon so it would also be good for us to know if you are experiencing problems here so we get things working as smoothly as possible. Cheers, Spencer. On 25 Apr 2015, at 14:23, Zhicheng Wang <wangzhicheng09@gmail.com<mailto:wangzhicheng09@gmail.com>> wrote: Hi nektar++ users and developers, I 'm using the latest nektar++ version. However when running the TurbChFl_3DH1D.xml example and using FieldConvert calculating vorticity or Qcriterion, I got errors as "ERROR: Element u_33 is 0 from dgetrf". I have checked the velocity and pressure field, it is correct, so if there is some inconsistency in FieldConvert for 1D homogeneous problem? _______________________________________________ Nektar-users mailing list Nektar-users@imperial.ac.uk<mailto:Nektar-users@imperial.ac.uk> https://mailman.ic.ac.uk/mailman/listinfo/nektar-users Spencer Sherwin McLaren Racing/Royal Academy of Engineering Research Chair, Professor of Computational Fluid Mechanics, Department of Aeronautics, Imperial College London South Kensington Campus London SW7 2AZ s.sherwin@imperial.ac.uk<mailto:s.sherwin@imperial.ac.uk> +44 (0) 20 759 45052