> ## Documentation Index
> Fetch the complete documentation index at: https://prod-mint.classiq.io/llms.txt
> Use this file to discover all available pages before exploring further.

# qDrift

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  Open this notebook in GitHub to run it yourself
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The `qdrift` function implements the qDrift Trotter evolution of Ref.[ \[1\] ](#qdrift).

Function: `qdrift`

Arguments:

* `pauli_operator`: `CArray[PauliTerm]`,
* `evolution_coefficient`: `CReal`,
* `num_qdrift`: `CInt`,
* `qbv`: `QArray[QBit]`,

## Example

```python theme={null}
from classiq import *


@qfunc
def main(qba: Output[QArray[QBit]]):
    allocate(2, qba)
    qdrift(
        Pauli.X(0) * Pauli.Y(1) + 0.5 * Pauli.Z(0),
        evolution_coefficient=2.0,
        num_qdrift=5,
        qbv=qba,
    )


qmod = create_model(main)
qprog = synthesize(qmod)
```

## References

<a name="qDrift">\[1]</a> E. Campbell, Random Compiler for Fast Hamiltonian Simulation, (2019). [https://arxiv.org/abs/1811.08017](https://arxiv.org/abs/1811.08017)