Add fix and unfix functions for parameter fixing and unfixing
#248
| Job | Run time |
|---|---|
| 3m 16s | |
| 2m 58s | |
| 3m 49s | |
| 3m 47s | |
| 4m 5s | |
| 11m 39s | |
| 2m 31s | |
| 3m 35s | |
| 6m 11s | |
| 41m 51s |