# Issues Solving Pure Neumann Problems in dolfinx

**URL:** <https://fenicsproject.discourse.group/t/issues-solving-pure-neumann-problems-in-dolfinx/10468>\
**Category:** dolfinx\
**Created:** [February 17, 2023, 9:32pm UTC](https://fenicsproject.discourse.group/t/issues-solving-pure-neumann-problems-in-dolfinx/10468 "2023-02-17T21:32:50Z")\
**Posts on this page:** 1\
**Showing post:** 7

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**Author:** ![Daniel.Baker](https://avatars.discourse-cdn.com/v4/letter/d/b9e5f3/32.png) [@Daniel.Baker](https://fenicsproject.discourse.group/u/Daniel.Baker)\
**Post date:** [May 1, 2024, 12:49pm UTC](https://fenicsproject.discourse.group/t/issues-solving-pure-neumann-problems-in-dolfinx/10468/7 "2024-05-01T12:49:21Z")

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That’s cheating. This is a baby problem, where we already know the answer. The motivation for this is a somewhat more complicated problem, where we don’t know the answer. The version of this I am trying to solve (another baby problem…) is here

> [@Implementing a potential problem with a current condition](https://fenicsproject.discourse.group/t/implementing-a-potential-problem-with-a-current-condition/14491):
>

As I understand it, the old fenics had the capability to introduce additional constraints into the PDE, which fenicsx apparently doesn’t allow. Is there some workaround for this which doesn’t rely on already knowing what the solution in the null space looks like?

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