# Time, Accuracy, Speed Analysis (TAS)

```{highlight} none
```

Below is the guide to running TAS using ex13, which is a Poisson Problem in 2D and 3D with Finite Elements:

1. Compile `ex13.c`

> 1. This example source file, and the corresponding `makefile` are located in `PETSC_DIR/src/snes/tutorials/`
>
> 2. Compile with the command:
>
>    > ```console
>    > $ make ex13
>    > ```

2. Run ex13 with the following command:

   ```
   mpiexec -n 2 ./ex13 -log_view :/home/<user name>/PETSC_DIR/lib/petsc/bin/ex_13_test.py:ascii_info_detail \
     -dm_distribute \
     -dm_plex_box_faces 8,8 \
     -potential_petscspace_degree 1 \
     -snes_convergence_estimate \
     -convest_num_refine 5
   ```

3. A log file in the above directory called `ex_13_test.py` should now be present. This is also the same directory that contains the TAS python3 script `petsc_tas_analysis.py`

4. Now run `petsc_tas_analysis.py`:

   ```
   ./petsc_tas_analysis.py -f ex_13_test
   ```

5. You should see something similar to the following in your terminal window:

   > ```{literalinclude} exampleTASOutPut.txt
   > ```

6. Finally the graphs will appear in the subdirectory `graphs/`

For more detailed help in using TAS:
: 1. See detailed user's guide
  2. On the command line use `./petsc_tas_analysis.py -h`