# Setting inflow with a variable expression? **URL:** \ **Category:** Just Starting\ **Created:** [19 August 2014 18:43 UTC](https://pyfr.discourse.group/t/setting-inflow-with-a-variable-expression/46 "2014-08-19T18:43:54Z")\ **Posts on this page:** 3\ **Page:** 1
**Author:** ![Anthony\_Ashley](https://avatars.discourse-cdn.com/v4/letter/a/c2a13f/32.png) [@Anthony\_Ashley](https://pyfr.discourse.group/u/Anthony_Ashley)\ **Post date:** [19 August 2014 18:43 UTC](https://pyfr.discourse.group/t/setting-inflow-with-a-variable-expression/46/1 "2014-08-19T18:43:54Z")
Hello, I was wondering if it is possible to specify an inflow (or outflow) boundary condition with a variable expression, similar to how one can be used in the soln-ics? If I try this in the .ini file: > [soln-bcs-inflow] > > type = sub-in-frv > > rho = rho0 > > u = 1.0-(0.2\*y)^2 > > v = v0 I receive the error > NameError: name ‘y’ is not defined Thanks for any help in this matter! Anthony Ashley Rensselaer Polytechnic Institute PhD Student, Aerospace Engineering ---
**Author:** ![fdw](https://avatars.discourse-cdn.com/v4/letter/f/a587f6/32.png) [@fdw](https://pyfr.discourse.group/u/fdw)\ **Post date:** [19 August 2014 18:46 UTC](https://pyfr.discourse.group/t/setting-inflow-with-a-variable-expression/46/2 "2014-08-19T18:46:18Z")
This is not currently possible. While expressions such as:   u = 1.0\*gamma^2 are permitted those which would give each point in space a different value of u are not supported. It is, I believe, on the to-do list. Regards, Freddie. ---
**Author:** ![p.vincent](https://yyz2.discourse-cdn.com/free1/user_avatar/pyfr.discourse.group/p.vincent/32/225_2.png) [@p.vincent](https://pyfr.discourse.group/u/p.vincent)\ **Post date:** [19 August 2014 18:48 UTC](https://pyfr.discourse.group/t/setting-inflow-with-a-variable-expression/46/3 "2014-08-19T18:48:54Z")
Hi Anthony, Thanks for your interest in PyFR. I’m afraid this is not a feature at the moment - but it is definitely on our todo list! Cheers Peter