******************* This email originates from outside Imperial. Do not click on links and attachments unless you recognise the sender. If you trust the sender, add them to your safe senders list https://spam.ic.ac.uk/SpamConsole/Senders.aspx to disable email stamping for this address. ******************* Dear all, I am trying to perform a Floquet stability analysis using Nektar++ but facing some errors. I have generated a two-dimensional periodic base flow of flow past a cylinder, at slices, and using the same in an XML file for stability analysis. Below are the output and some relevant sections of the XML file. It would be of great help to fix the issue or point to some already set-up example cases for the Floquet stability analysis. #IncNavierStokesSolver Cylinder_Floquet.xml read base flow file Cylinder-Base_0.chk read base flow file Cylinder-Base_1.chk read base flow file Cylinder-Base_2.chk read base flow file Cylinder-Base_3.chk read base flow file Cylinder-Base_4.chk read base flow file Cylinder-Base_5.chk read base flow file Cylinder-Base_6.chk read base flow file Cylinder-Base_7.chk read base flow file Cylinder-Base_8.chk read base flow file Cylinder-Base_9.chk baseflow info : interpolation order 0, period 0.00111111, periodicity yes baseflow info : files from 0 to 9 (skip 1) with 10 time intervals Fatal : Level 0 assertion violation Expect to have three velocity fields with homogenous expansion XML file snippet: <SOLVERINFO> <I PROPERTY="SOLVERTYPE" VALUE="VelocityCorrectionScheme"/> <I PROPERTY="EQTYPE" VALUE="UnsteadyNavierStokes" /> <I PROPERTY="EvolutionOperator" VALUE="Direct" /> <I PROPERTY="Projection" VALUE="Galerkin" /> <I PROPERTY="TimeIntegrationMethod" VALUE="IMEXOrder2" /> <I PROPERTY="ModeType" VALUE="HalfMode" /> <I PROPERTY="Driver" VALUE="ModifiedArnoldi" /> <I PROPERTY="Homogeneous" VALUE="1D" /> </SOLVERINFO> <PARAMETERS> <P> TimeStep = 0.001 </P> <P> NumSteps = 1000 </P> <P> IO_CheckSteps = 100 </P> <P> IO_InfoSteps = 100 </P> <P> Re = 188 </P> <P> Kinvis = 1./Re </P> <P> kdim = 4 </P> <P> nvec = 2 </P> <P> evtol = 1e-6 </P> <P> N_slices = 10 </P> <P> LZ = 2.4166 </P> </PARAMETERS> <EXPANSIONS> <E COMPOSITE="C[0]" NUMMODES="7" FIELDS="u,v,p" TYPE="GLL_LAGRANGE" /> </EXPANSIONS> Thank you in advance. Regards, Nandan Sarkar PhD candidate Dept. of Mechanical Engineering Indian Institute of Technology Kharagpur India 721302