# Getting iter/convergence info from hung solver

**URL:** <https://community.freefem.org/t/getting-iter-convergence-info-from-hung-solver/2221>\
**Category:** General Discussion\
**Created:** [January 15, 2023, 11:46am UTC](https://community.freefem.org/t/getting-iter-convergence-info-from-hung-solver/2221 "2023-01-15T11:46:02Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![marchywka](https://avatars.discourse-cdn.com/v4/letter/m/ee59a6/32.png) [@marchywka](https://community.freefem.org/u/marchywka)\
**Post date:** [January 15, 2023, 11:46am UTC](https://community.freefem.org/t/getting-iter-convergence-info-from-hung-solver/2221/1 "2023-01-15T11:46:02Z")

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I’ve setup a simple problem again ( 2 cubes in flowing air )  
but with a different model equation. In setting it up, I have a few issues  
with boundary conditions. In one case, the thing seems to run forever  
with no progress result and no idea how to determine if it is stuck, hit  
some limit cycle, or is slowly improving. Setting “verb=1” provided  
nothing useful. Right now I need to just guess on formulation and BC  
code. Is there some way to get more diagnostic info? Thanks.

//solve Stokes (ux, uy,uz, p,q, vx, vy,vz, solver=Crout) // oom  
//solve Stokes (ux, uy,uz, p,q, vx, vy,vz,solver=sparsesolver)  
solve Stokes (ux, uy,uz, p,q, vx, vy,vz,solver=CG,verb=1)

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<div class="post-metadata">

**Author:** ![marchywka](https://avatars.discourse-cdn.com/v4/letter/m/ee59a6/32.png) [@marchywka](https://community.freefem.org/u/marchywka)\
**Post date:** [January 15, 2023, 12:17pm UTC](https://community.freefem.org/t/getting-iter-convergence-info-from-hung-solver/2221/2 "2023-01-15T12:17:43Z")

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It looks like putting braces around the parameters helped 🙂  
At least now it is producing output and I can play with the model  
Is there some way to get it to dump what it thinks the parameters are? lol

//solve Stokes (ux, uy,uz, p,q, vx, vy,vz,solver=sparsesolver)  
solve Stokes ([ux, uy,uz, p],[vx, vy,vz,q],solver=CG,verb=1)

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<div class="post-metadata">

**Author:** ![cmd](https://yyz2.discourse-cdn.com/flex030/user_avatar/community.freefem.org/cmd/32/67_2.png) [@cmd](https://community.freefem.org/u/cmd)\
**Post date:** [January 16, 2023, 12:23pm UTC](https://community.freefem.org/t/getting-iter-convergence-info-from-hung-solver/2221/3 "2023-01-16T12:23:18Z")

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you can always use something like:

```auto
cout << "VAR1 = " << VARIABLE1 << ", VAR2 = " << VARIABLE2 << ... << endl;

```

to print out parameters at any point in your code.