(NLATTICE-target)=
# NLATTICE
```{tags} Quantum Mechanics, Gas Phase Quantum Mechanics
```

Send number of lattice points.



## >NLATTICE

Send number of lattice points

**Datatype:** `MDI_INT`  
**Quantity**: `1`  

 This command, along with the [>CLATTICE](CLATTICE) and [>LATTICE](LATTICE) commands, allows the driver to assign a lattice of point charges to an engine, which incorporates the effects of these charges in all further calculations. 
After sending this command, the driver sends the number of point charges to the engine. This command must be sent before either the [>CLATTICE](CLATTICE) or [>LATTICE](LATTICE) commands can be sent.

This command is primarily intended for use with gas-phase quantum mechanics codes. For an alternative command that is more appropriate for plane wave quantum mechanics codes, see the [>POTENTIAL](POTENTIAL) command.


### Examples


::::{tab-set}

:::{tab-item} Python
:sync: python

```python
import mdi

# connect to the engine
mdi_engine = mdi.MDI_Accept_Communicator()

# send the number of lattice points to the engine
nlattice = 10
mdi.MDI_Send_Command(">NLATTICE", mdi_engine)
mdi.MDI_Send(nlattice, 1, mdi.MDI_INT, mdi_engine)

```
:::

:::{tab-item} C++
:sync: cpp

```cpp
#include "mdi.h"

// connect to the engine
MDI_Comm mdi_engine = MDI_Accept_Communicator();

// send the number of lattice points to the engine
int nlattice = 10;
MDI_Send_Command(">NLATTICE", mdi_engine);
MDI_Send(&nlattice, 1, MDI_INT, mdi_engine);

```
:::

::::