******************* This email from 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, I’m working on a multigrid code and I’m wondering if there’s any way to get Galerkin coarse grid operators. The context is that I’m writing a Newton-multigrid type method, so I’m linearizing my PDE around the current iterate using automatic differentiation and then building the levels. I saw a 2016 paper which uses the coarsen_form function to get the coarse grid form, but that doesn’t seem to work anymore (and I’m not sure exactly what it does). Sincerely, Max Heldman