###MrBayes

Currently is installed MrBayes 3.2.6 version working with mpi 2.0

This one of the programs that we recommend to use with [[users:guides:screen | screen]].

Once entered in cluster-ceab we open a screen session (for further details see [[users:guides:screen | Screen]])

**without mpi**

Init a qlogin 
```
qlogin -l h_vmem=4G 
```
and once in the node

```
/home/soft/mrbayes-3.2.6/src/mb
```

**with mpi**

init a qlogin with the number of processors with mpi environment 

```
qlogin -l h_vmem=4G -pe mpi 6
```
to use mpi we need to declare two variables first, just copy this two lines in the terminal.

```
PATH=/home/soft/openmpi-2.0.1/bin:$PATH
LD_LIBRARY_PATH=/home/soft/openmpi-2.0.1/lib:$LD_LIBRARY_PATH
```

and then run the program with the number of processor reserved in the qlogin:

```
$ mpirun -np 6 /home/soft/mrbayes-3.2.6/src/mb
 

                            MrBayes v3.2.6 x64

                      (Bayesian Analysis of Phylogeny)

                             (Parallel version)
                         (6 processors available)

              Distributed under the GNU General Public License


               Type "help" or "help <command>" for information
                     on the commands that are available.

                   Type "about" for authorship and general
                       information about the program.

MrBayes > 
```

if you have started screen you can close this terminal while the program is running and reatach it later to see if is finished. 

**Don't forget to close the screen session when finish:**

Close MrBayes with **q** and then **exit** twice, the first one to finish the qlogin and free the reserved resources and the second one to clos the screen terminal.