Hi Alessandro, Could you tell me the command and Nektar++ version you are using? The interppoints module is usually called like this, the number of points in each direction should be greater than 1, FieldConvert -v -m interppoints:fromxml=wing.xml:fromfld=wing_${n}.chk:box=301,301,601,-0.5,2.5,-0.5,1.5,0,5.5 interp.plt Cheers Ankang ________________________________ From: nektar-users-bounces@imperial.ac.uk <nektar-users-bounces@imperial.ac.uk> on behalf of Alessandro Alberto de Lima <aalima@usp.br> Sent: 02 February 2022 16:19 To: nektar-users <nektar-users@imperial.ac.uk> Subject: [Nektar-users] problems with FieldConvert This email from aalima@usp.br 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. Hi Guys. I'm trying to get lines, planes and boxes interpolated without using paraview, direct from FieldConvert but I'm getting a "Segmentation fault". My case is a 3DH1D simulation. Thank you. Alessandro